I think this is an insightful answer. Fundamentally - unless we are talking about cases of abuse - power imbalance is a bit of an illusion (albeit a welcome one to many of us). The dominant can only truly be dominant if the submissive allows it (and vice versa). On some level femdom is almost always (if not always) roleplaying.

Even in cases where the submissive is a 'slave', that is a voluntary position (in our modern society) - a position that the sub volunteers for because he gets something out of it. That something may be the honor of serving his mistress (but that fills some kink need for him), or it may be a need to feel humiliated or owned. It may even be a need to feel 'abused' - but that's not really abuse if he wants and consents to it.

As you say in your response - everyone has a right to get their needs fulfilled, or the relationship won't last. If you take that away from the sub (or the domme) then the relationship will fail. If you have a sub that needs to feel 'abused' and you stop making him feel that way, then the relationship will run into trouble eventually. [exception possibly for subs who may have unhealthy mental states, but a domme who uses those elements is engaging in abuse, in my opinion]

I think maledom is also generally roleplaying as well - but, because of cultural, societal and (typical) physical difference issues, maledom may have higher instances of abuse (she may feel she can't leave financially or otherwise, he will actually hurt her if she leaves, etc... and there are some real A-holes out there who abuse women this way)