Reaction?  The reaction you'd get would probably be about the same as if you wore a regular tank top leotard, i.e. not much.  If you're in adult open classes, you can wear much more "nonstandard" things and still get little reaction.  I've seen a guy who wears pink tights and his hair in a bun, and he gets no reaction.  However, teachers might talk about you behind your back if you do that --- but just as an off-hand way to pass a dull moment.

Women wearing pointe shoes whos feet aren't strong enough get MUCH more of a reaction from teachers and students who know better.