I have any issue with anyone encouraging injury.
I have a problem understanding how you can encourage someone to injure another player legally, though.
If it's within the rules, and the game encourages big hits and aggressive play, then why is a coach at fault for playing by the rules and encouraging aggressive play.
The players are already going to try and play within the rules and they are already going out trying to knock people out, regardless of incentives.
Tell me this. If a coach gives a pregame speech about how he wants his team to go out and knock people out, tear them apart, blah blah, but he doesn't give a cash incentive, is it ok to you?