I don't visit the cinema often any more and I don't have any worries with wearing out and about, but heck yeah I'd wear at the cinema. It's a perfect opportunity, dark room, good movie, all that soda.
Some plastic pants might be helpful just in case of leaks though I would not recommend pooping as it was suggested above, unless you are actualy bowel IC and willing to miss some of the movie to change. Even with good plastic pants that smell will only be covered for a bit and you are in close proximity to other people, it would be highly inconsiderate to subject them to that.