Interesting. Why would a dealer care if someone is winning? Usually big winners tip the dealer handsomely.
Card counters (and advantage players in general) are much less likely to tip well compared to the average gambler. The sort of people who think they're making money on a game also tend to recognize that tips cut into profits.
Dealers care because the casino cares, and pays them to care.
Having never been to a casino, I've always wondered, on what grounds will a casino ask you to leave? Just that it's private property and they no longer want to serve you? It makes it pretty transparent that the house always wins, and even when they don't they can ask you to leave, ensuring they always win.
I love the implication when someone is asked to leave but, "the rest of you, you losers can stay."
The casino has no problem just telling you, "you're too good for us". Depending on the situation and the mood of everyone involved, you may be told you're welcome to play other games, or you might just get trespassed.
Note that due to a New Jersey court ruling, casinos in Atlantic City actually can't bar people for counting cards. In general the game conditions there are worse to make up for that.