To a non jew, a jew is a jew. I personally have been called “a hasid” by non jews and I look nothing like a chassid. I’ve been called Rabbi too and I do nothing to perpetuate such a myth.
Yes, its true that you cant lump “all hasids shop there” and “all hasids are on govt programs” together, and it is a ridiculous comment, for anyone to make. What is important is why someone would make such a statement and why they believe it to be true. When confronted with situations such as presented, I dont even try to answer “well, every group has its bad apples” or anything similar. I tackle it head on. I would answer, really, all hasidic girls shop there, you keep tabs on hasidic girls shopping habits that you can make such a statement?
Off the topic: It sounds a bit funny that this person thinks (in your own words) that hassidic girls are cute. I would have shomrim keep an eye on this guy. Apparantly he keeps tabs on chassidish girls. He sounds like a pervert.