LOL. I knew a guy who always wore his running shoes while traveling, with dress shoes or whatever other footwear he had in his bag.

His logic: he can go find a passable pair of dress shoes in any city, but *nobody* ever has his perfect make/model/size of running shoe. He also swore by the fact that his running shoes didn't feel right until he had 40-50 miles in them and didn't want to have to break in a new pair on a trip, even if he managed to find them somewhere