It's really not the sales lady's decision. If she doesn't want to wear a bra then I don't think she should have to. I would have her try the dress on have someone like yourself or a friend give an honest opinion about how it looks. I don't think it's a huge deal but if it is you can just get Nippies or something of that sort. (Nippies are little sticker things that cover the nipple)
I'm all for a woman's right not to wear a bra
