Supporters haven't seemed to be concerned enough to stay away from games in the past so maybe hasn't really been an issue. Most players don't earn anywhere that amount and have short footy careers. And they entertain 100s of thousands of people. I haven't seen a problem, the game could support these salaries, in the AFL at least. Obviously now is an unprecedented situation. No one believed a month or two ago that a whole season would be wiped out. Obviously the game as far as money involved is going to look completely different in the future.
