In all, every casino is unique in their different ways, we the gamblers are the ones to search and choose one that really meets our expectations and stick with them, there is no perfect system anywhere in the world.
Problem here is that we cannot stick to such sites even though we like them a lot due to limits/restrictions on certain popular sports which is why we end up shifting to other platforms.
Sucks that so many sportsbooks chase away winning gamblers quickly, but it makes sense from a financial point of view.
The only thing to do with that restriction is to choose a reputable sportsbook that allow us to bet without any worry about such matter. To many reputable casino exist at the moment so there's nothing to worry for picking up those especially if we are here since we can browse those reputable casino offering good service to the community.
I don't know if they really chase away those winning gamblers since I don't encounter it so far but one thing is for sure they need those guys to gamble back on their casino again since they know that not all the time those guy will always win and there's a lot of chance that they can get a profit from those people especially if they got hook and lost a lot of money unto their casino. This is how business should be and if there's really a cases that they drive out the winners then maybe they are a scam casino and doesn't want their gamblers to win so we should avoid that.