Many vendors purport to be dealing with issues, but the reality is that they still seem to want to keep the trolls "in the game", if perhaps a bit less disruptive. At the same time, they're often quite quick to jump on those they suspect are involved in fraud, etc, so it seems reasonable to think that they have means to ban and to some extent track those that are involved in activities that affect the bottom line.
So the big question is: when does "bad behavior" become bannable behavior? Is it only when money is involved? There's also cases where botting, hacking, etc have also resulted in a permanent ban. Beyond that, it seems that only extremely bad publicity can lead to a permanent ban.
However, we have a huge problem in many games with those whose sole purpose is to troll others. Throwing games, cursing out other players for no reason, playing random noise through the mic, there are some people who live simply exist to screw with others. It shouldn't be that hard to identify them, so why can't we have legitimate consequences to deal with them?