Dana has worked for the UFC for 20 years, he works more than full time hours according to many accounts as well as weekends and holidays. Look at CEO pay, his isn't out of line for the amount of growth he is responsible for.
Compare that to most UFC fighters, who are with the company 3-5 years, and fight 2 to 3 times a year.
I think it is more than fair. I am not saying UFC fighter wouldn't be justified in wanting more money, but ya Dana makes more than any fighter because he put more into the company than any fighter, I would say Chuck is a close 2nd, which is why he gets paid to be a spokesperson even though no one can understand him when he talks.
Everyone else leaves to go pursue something better while Dana sticks back and tries to make the UFC better. That's why he gets those big dollars.