A. Why on EARTH would the UFC give a cut of the sponsorship money to smaller-named fighters? Literally everything about fighter pay is dictated by demand/profitability calculus. What makes you think the UFC would adopt some Commie redistribution scheme? Goodness of Dana's heart?
B. The sponsorship deals will all be outside the cage. For a low-profile fighter with no name/face recognition outside of the cage, this effectively limits all lucrative sponsorship opportunities until the fighter becomes famous, which may be years, but probably never. Meanwhile, the UFC will make millions.
C. The UFC has every legal right to require its competitors to wear uniforms, and to control advertising space on those uniforms, and to collect revenue for that advertising space. Is it right? That's another story. Personally, I think it's downright evil considering most fighters make less than full-time baristas.