The title says it---have you ever bought a bike simply because it spoke to you even though you had no real practical use for it? For example, I spotted a single speed that just really grabbed me at a local LBS, yet I live in totally hilly terrain---I ride a road bike now, and let's just say I use the gears to their fullest! I walk out my front door and I'm climbing hard within the first 1/3 mile just to get anywhere.
But still, I want this other bike---I think the stealthy simplicity of it appeals to me. I'm getting plenty of fitness out of my road bike in my hilly locale so I don't think at my age (50) I need to be grinding up these hills on a single speed, but still....i want it