You may not think about carrying a whole extra snare to a gig, but what if you broke a lug casing on the snare? This happened to me once, and I must have hit the ultimate rim shot or something. Replacing a broken head is one thing (always carry extra heads as well), but if you crack a lug casing, you’re pretty much screwed.
So avoid any further drummer jokes, and make it habit to carry around two snare drums. Consider it insurance. Plus, you can do the Steve Jordan thing and switch snares during a set.