I too, was hoping for a townie.
I think they are great city bikes because they are reliable, comparatively light weight, can be had for pretty cheap, very low maintenance.
Also, they are great for the beginning bike hobbyist. Without dérailleur, the bike is less complicated. Or at least less intimidating from a mechanical standpoint.
Fixies have a 'get up and go' feel about them. It may not be a 'logical' reason, because there is nothing stopping you from hopping on your road bike and doing the same thing, but something about riding a fixie just requires less thought.
I don't think about it at all, I just get on the bike and go. Don't worry about water bottles or lycra, or special shoes.