I head to the door and put on my shoes on.

"I'm going to Zehrs," I tell my wife, referring to our local supermarket. "Any special requests for dinner?"

"Oh that sounds nice!" she replies. "How about something Mediterranean?"

I frown in consternation. Could we afford to buy goat cheese at the last minute? The price of dairy fluctuates so much, and it's the peak season for groceries. Normally, we put in our grocery order months in advance to get the best price.

"I'll see what I can find," I reply. "Would Mexican be all right, if that's all they have?"

"Sure," she says. She is quick on the reply. I sense a touch of disappointment in her voice. She likes Mexican food, but I could tell she really had her heart set on Greek or Italian.

---

I walk up and down the aisles at Zehrs, looking out for sale items. There are none.

I decide to check out Sobeys instead. They don't have as much selection and the store layout is a bit confusing, but I might find better prices.

At Sobeys, I am surprised to find that their prices are exactly the same as at Zehrs. They have a few items on sale. Otherwise, it is all the same.

It is as though Zehrs and Sobeys watch each other's prices on grocery items so that they can match each other.

---

Still at Sobeys, I have already ruled out the Mediterranean food -- prices are just too high. I have been here for 15 minutes and my cart is still empty. I need to have dinner ready in an hour. I shouldn't have waited this long to shop.

The beans are $8.74 a can. Just last week, they were only $2.35. Is it inflation? I thought the inflation rate was holding steady at 3% a year. At that rate, such a price increase should occur over a period of about 50 years, not one week. Odd.

I notice a stock boy replacing items on a shelf nearby and walk over to him.

"Excuse me," I ask. "How come the beans are so much more expensive than last week?"

"Supply and demand," he replies with a smirk. "We still had 156 cans of beans last week. Now there are only 12 cans left, so the price went up."

I ignore his condescending tone of voice and ask, "Why would the price go up? They're still the same beans."

"Well," he continues, "there are people who wait until the last minute to do their grocery shopping, and they will always buy beans no matter what the price. If you absolutely must have chili tonight and have no other option, you'll pay the $8.74."

I am incredulous. I look over at the beans and wonder who in their right mind would pay $8.74 for one can. I notice an impeccably dressed man in a business suit and expensive shoes, walking over toward them. He picks up two cans and puts them in his cart -- without even looking at the price.

"Excuse me," I ask him. "Did you notice how much those beans cost?"

"No idea," he replies. "It doesn't come out of my pocket. It's for a corporate function. I'll just keep my receipt and get reimbursed."

"They're $8.74 a can!" I exclaim.

He looks surprised. "Really?" he replies. "That's a bargain! Three months ago, I paid $14.00 for the same beans. It was the last can they had, but I just had to have it. I was lucky to get it."

As the businessman walks away with his prize, the stock boy hurries over to the shelf with the beans. He puts up a new price tag. It reads $9.57.

"Only 10 cans left," he explains. "Price just went up."

---

I hurry over to the Mexican foods section, determined to find something for dinner. Tortilla shells are on sale: $1.49 for a package, including a coupon for a discount off shredded cheese. Perfect! I'll make quesadillas.

I get to the cash and put my tortilla shells on the conveyor belt. They come up as $3.28.

"Excuse me," I say to the cashier. I notice that I seem to be saying that a lot today. "The tortilla shells are $1.49, not $3.28. That's what the price tag on the shelf says."

"Uh, yeah," she replies, rolling her eyes as though I am the hundredth person today to point out this discrepancy. "The price went up by the time you walked over here to pay for them. They're $1.79 now."

"How come the price went up?"

"Supply and demand. We still had--"

I cut her off. "Okay, okay, I get it. Supply and demand. Fine. But you said they're $1.79 now. How come it's ringing up as $3.28?"

She sighs with exasperation. "Sir, do you want the tortilla shells or not?"

"Yes I do," I reply. "I'm just wondering why they're coming up as $3.28, if they're being advertised as $1.49 or $1.79 or whatever."

"Look," she explains. "You've got your fuel surcharge, $0.45 -- that's for the truck that delivered them here. You've got your concession fee recovery fee, $0.28 -- that's for the rent we pay to build our store here. There's also the special security charge, $0.26 -- we have to pay a security guard to look out for possible threats. Don't forget the administration fee, $0.30 -- you can avoid that next time, by ordering online and going through the self-checkout. And of course, there's tax. $0.20. That's a government-mandated charge and we have no choice but to comply!"

"There's no tax on tortilla shells," I point out weakly. "They're a basic food item, not a snack item."

"That's true, but there is tax on the fees and surcharges. Now do you want the tortilla shells or not?"

I am defeated. I hand over $3.28.

"Oh wait, I forgot to ring in your shredded cheese," she says, reaching for the other item on the conveyor belt.

I hand her the coupon for the cheese. She frowns at it and hands it back to me. "This coupon is only valid on Saturday nights. Today is Monday. And you need to provide two weeks' advance notice to use it."

---

I get home with my groceries. I have just enough time to make the quesadillas.

I tear open the package of tortilla shells. It is empty!

Back to Sobeys I go. This time, I head straight to the customer service desk.

"There are no tortilla shells in this package!" I exclaim angrily, waving the empty wrapper around in the air.

"Yes sir, I know," the cashier explains. "We oversold our tortilla shells. Unfortunately, we don't have enough tortilla shells to fill all the packages tonight."

"Then why would you sell me any at all?" I reply.

"Sometimes people buy tortilla shells but leave them behind in the store. If we have 180 packages for sale and sell 200 of them, and 10% of the shoppers leave them behind, we can still accommodate everybody."

"But you still get paid for 200 packages," I reply.

"Exactly."

"Why would anybody pay for tortilla shells, then leave them behind?"

"I don't know. It happens."

"What about when more than 180 people actually decide to take their groceries home with them? What then?" I ask.

"Well, that's what happened today, and you ended up with an empty package. Don't worry, we will get more tortilla shells delivered in the morning, and we can give you a fresh package at that time."

"Tomorrow morning? I need these for dinner tonight!" I exclaim. I'm really mad.

"Sorry," she says with a shrug. "It happens. First come, first served. You shouldn't have waited so long."

"But you knew the package was empty when you sold it to me!"

"We took a chance that you wouldn't use it."

"Okay," I reply. "Just give me my money back. I'll go to Zehrs and buy the tortilla shells there."

"I'm sorry sir, these tortilla shells were a last-minute purchase and are completely non-refundable. I can give you another package tomorrow. If you prefer, I can give you a coupon that you can apply toward any Mexican food item in the next year. There is a $1.10 charge to redeem it and there are some restrictions."

"Let me guess, two weeks' advance notice and only valid on a Saturday night, right?"

She looks at me with surprise. "That's right! How did you--"

"Never mind," I reply. "Just give me the coupon and I'll be on my way."

---

I return home empty-handed.

"When are we having dinner?" my wife asks me.

"Tomorrow morning," I reply. "If we're lucky."