What’s convenience worth, anyway?

About 45 cents, if today's example is to be believed. There's a little store in the lobby of the building I'm working in this week that sells 20 oz bottles of pop for 1.95. But go around a corner, through a couple of doors, no more than 50 steps away, and you can get the same out of a vending machine for $1.50. Granted the vending machine is outdoors, in a weird little courtyard that totally had to be where the smokers hung out before the building went smoke free. So if it was raining, I could see how it might be worth the extra few cents. But there's probably a psychology at work here, where people might not even even seek out the vending machine, despite a decently sized with pointing to the first door you have to go through, when a cooler with soda and shelves of snacks are right there in front of their eyes.