I do not understand how SAs can be arrogant. I'm sure most of them work on some kind of comissional basis so they definitely care for you buying something or not. Its sheer arrogance to assume by someones appearance whether or not he has got money to spend. Incidents like these make me want to visit these particular shops again, dressed like a hobo, only to complain to the shop/brand owner while waving with a 500 € bill that I WAS going to spend there.
Unfortunately I myself have experienced this myself often enough. Bein far younger than their usual customers and male, the probably think it's just the next kid looking to get himself a free wearing of Le Male.
Although all of these SAs in my experience were uptight middle aged women.
Sorry for the ramble but this is one of the worst side effects I have encountered regarding this hobby and I just wanted to chime in.
You should definitely not let this kind of behaviour stay uncommented!