To do the same whenever they feel they've been screwed, by any company.

Because just because it's"legal", does not mean that a Court can't interfere: the Law recognises (and is designed as a tool to protect) the interests of minority shareholders. The Law knows that the majority can in fact be oppressive of theose interests, and yet be within "the black letter of the Law": thus, the Corporate Statutes expressly enable Courts to interfere, not just in cases of bald illegality, but also to preserve fairness: even where the majority shareholders have the legal power to act as it has.

But it's the job of the smallholders themselves to get the Law involved - this is not a criminal matter - so the "Authorities" aren't concerned..