The non-profit can still have rules in place on who is accepted as members and who isn't, as long as the rules don't break any laws (discrimination etc.). They

The non-profit can still have rules in place on who is accepted as members and who isn't, as long as the rules don't break any laws (discrimination etc.). They also can have a mission statement and rules that are not up for vote. They can have members enter a contract with the non-profit when joining as a member. Also, depending on who's "taking over" and who's "taken over", it can be argued that if the majority of members that provide the majority of the funding to the non-profit, shaping the non-profit according to the majority of its members is the right thing to do. If there's too much differences in opinion, the non-profit can also split any time.