The founders typically don't get to choose, they have the obligation to respect minority investors' interests and sell to the highest bidder. Also the gold standard is going public, which would make figuring out who's "bad" pretty hard.
Then again, they don't get rich by cheating, abusing or whatever, they build a legal thing and sell it. You wouldn't go after a knife maker if someone used his knife to stab someone.
If they don't get to choose, they already gave up control in an earlier stage. Just as with going public, they're relinquishing partial or total control of their company and this is a moral decision.
If you make a successful crowdsourced reviews website by building trust over time with contributors and users, and by any mechanism it ends up getting owned by an advertisement company that makes a business out of making it pay-to-win, should you not be held responsible?
I'm not talking about legal responsibility here, just moral responsibility. Ideally the former should follow the latter but it's not always the case.
You're making a case for stricter laws on dubious moral issues, not for startups as such.
Even then, has say Databricks or Canva been guilty of unethical conduct?