Bike-commuter's problem.... want to get some beer on the way home, my favorite beer shop (The Four Firkins) is sold out of the beer I want tonight (Surly Abrasive). They are the longer ride (=good) and much more fun to shop with, and I'm friends with the owner. Near my house is a grocery store that has the Surly, but it's a boring shop and no extra miles.
So much to consider.