There's actually a dom gap because of the amount of effort that goes into being a good active partner in bdsm. It's like being a DM playing out a scenario or situation.

My wife was a professional dom in another life before we met, and she talks about this a lot. People think it's just easy because all you have to do is treat the sub like a servant, but it's (according to her) really hard to do well. Coming up with a scene that's safe, respectful, and fun for everyone involved is work, and people who don't know what they're doing (or don't care about anything beyond their own satisfaction) can really fuck things up.