I think they do, if it means they can pursue their goals without threat of having their life's work destroyed.
I, for one, find the idea of doping and how to get around anti-doping schemes to be far more interesting than the pursuit of some arbitrary standard of excellent-but-didn't-cheat. Like blood doping is so different from things that are legal, like living in Denver!
Probably, but that's not the problem we're trying to solve. I don't care about the clean division, but it's fine that some people do. If you add a "doping" allowed division, the clean division is no worse off than it is now. It might be better, or it might not. But that's a secondary goal if anything.