On a recent trip I decided to buy a keychain. I like keychains, and the quality of keychains nowadays is poor at best so there's always a need for a new one. I used to have a keychain with a rotating potato in it, but it only lasted a day before the potato diappeared. Where it went I can't say, but the keychain was pretty boring without it. The potato was really the star of the show.
Anyway, I went up to a keychain stand and picked out a fine keychain. It was really shiney, so it kept my attention. Then I went to pay for it and the old lady running the stand said that it was a better deal to buy three keychains. The problem was that all of the keychains on the stand were Las Vegas keychains, so my selection was limited. But I picked out two other keychains and bought them and left. Later in the car, I did some quick math and found out that the price for three keychains was simply 3 times the price for one keychain so it didn't really pay to buy my keychains in bulk.
Keychain shopkeeps are a shifty bunch.