I side with them in relative terms. As in, I'd much rather see them get the money than the boys in suits. At the same time, I'm against the concentration of wealth at the top. So I'd much rather all of it be shared broadly, all the way down to the towel staff.
The median income in America for a single individual is roughly 30K a year. Not sure what the median is for the NFL, but I'd guess it's a hundred times that. The average CEO makes roughly 400 times the rank and file, and many times more beyond that than the working poor. I'd rather have egalitarian structures that radically shrink that gap. To me, a just, fair, moral and thriving society requires much, much higher wages for the bottom, and much, much lower wages for the top. Allowing for other factors such as time on the job, voluntarily increasing one's skill sets, education levels, etc. etc., I think the best way to go is to keep monetary compensation pretty close across the board.
And multi-million dollar salaries have to come from somewhere. All of that impacts salaries and prices elsewhere. Radically increase salaries at the top, and they have to be lowered somewhere else. And/or prices have to go up. They can't keep rising without repercussions. Money doesn't grow on . . . . etc. etc.