I would probably put you on the spot, too, if you came in for your spritz fix on a fairly regular basis (which to me once a week is); don't you feel shady using the demos as your personal stash?
IMHO, I don't think the "race card" is a valid play here because I, too, feel that I am being targeted as a potential shoplifter at times... and nothing drives me (and my money) away from a store faster than that. Often I just want to look around (or check out items mentioned on Specktra), and when I decide to buy, I spend a LOT, but I do not want someone following me around the store when I am just looking. And it would be rare for me to not be approached by *at least* 3 employees while browsing through a Sephora; so although it's annoying, I don't find it offensive even when their approach is lacking in tact or customer service. Some are just better at initiating communication with customers than others.
On the other hand, having worked in retail before I know that they are just doing what they were told/trained to do (and I think Shimmer's earlier post said that perfectly) and that shoplifting costs stores a lot of money and there is no "type" of person that you can look out for.
IMHO, I do think that perhaps you were being too sensitive to their comments.