Because you can look like a schmuck if you have a dork-o wallet. Nothing impresses the ladies more than pulling out a thick ugly wallet you've owned for 10 years, full of cards you can't even recall getting in the first place.
You have to put a little thought into it.
Same goes for dropping bucks at a bar, or *ahem*, for a lapdance, in a martini bar, etc. A few bills in a nice clip is more fitting.
Plus it's hard to show off a nice ass to the ladies if you have a big bulge on one side. (note: this is a plus in the front)
