Yes, he does, but the dancer also profits off the theater owner, because without use of the theater, the dancer makes fuck-all. Otherwise, the dancer would go dance in the park, or their own home, or anywhere else. The theater owner makes fuck-all without anybody to perform in the theater, and the dancer makes fuckall without somebody else providing a venue, handling the tickets, refreshments, etc.

And of course there's a tradeoff between how much each of them makes. I have no beef with private sector unions. By all means, negotiate as a bloc with your fellow dancers. But if you could do better without the theater, the theater owner would be bankrupt.

And yes, such power dynamics can exist. But in most capitalist nations, from Norway, to Canada, to Japan, to the United States, etc...there's a million ways to make a living. If you can't, and wind up in a trailer park complaining that Mexican immigrants took your job, then maybe your problem is more that you have nothing of value to offer anybody in exchange for putting a roof over your head.