There are sales associates who do not appreciate diversity when it comes to sexuality or sexual identity. It's not limited to attire. For the most part they just do their jobs, and, if they think they are funny they'll make some asshole comment after he or she leaves. Over the years I have had some snide comments made. However, when I use to buy alot of lingerie for my wife the sales associates, especially older women (30's-50's) fell over backwards to help me. Of course, since I was six foot and 175 pounds and I was buying for a five foot two woman of 115 pounds there was no hint the lingerie was for me. However, once when I went into a Catherine's to buy some full slips two sales associates acted as if space aliens had landed to abduct them. I had not even got ten feet into the store before I saw their angst and apprehension, and, I was neatly attired.
The worse was actually an internet order filled by the Kohl's store in Tukwila, WA. Not one of the ordered panties was sent, but, five wrong panties....not even close to the style and colors. It was obvious to me someone, presumably a woman, did not appreciate the order was by a male name. I sent a blistering letter to the head of Kohl's with a copy sent to the store manager. Many apologies and a partial refund. Of course, since our PayPal account is under my name, anytime my wife orders anything using the quick Paypal logo, it will show I ordered it.
I do think there are some young women entering the job market who have not encountered cross dressers, and, many times will be come flustered. And, as Sandi (#6) posted, some people are just plain ignorant and discriminatory.