Why would someone get upset over something that silly? (And what's the policy for, anyway? I've never encountered that before a dressing room.)

(And I've got friends who tell me horror stories about people who get nasty over how they bag their groceries after the fact. It's like, if you've got special needs on how you want your groceries bagged, do it yourself, or tell the person way before they put all your bags in your cart. Don't make them take the bags out and redo everything while you supervise and nitpick, that's just rude.)