A lot of ghetto types play it and they can get really hostile. One of them actually slapped me once. After that, it's middle-aged white males who think they are big shots at the blackjack table, and not only do they not know correct BJ strategy they don't realize SP21 strategy is radically different. Add to this all the index plays we use, where you end up playing something like the dealer does in very low counts.
Unfortunately most of the plays that drive them away are during counts where we would rather have them there eating cards!