Everyone has this idea of how to properly raise a child, what's right and what's wrong, and it's so different and there is no right or wrong way, really, as long as you teach and explain things to them.
I don't think a parent should be ashamed of or try to hide what they do from their kids. Especially high level MMA. Sure it's violent, but there's also a great deal of depth to the sport, discipline, hard work.
I know I watched wrestling when I was real young. What's the difference between pretending to hit each other and actually hitting each other, as perceived by a child?
I will say, when The Chris has his whole family there, that does seem distracting. It's not wrong tho. If that's what he wants and he's comfortable with it, then that's fine.