If a rancher gets above sale price for a steer, even a pitiful 5%, then that rancher is going to find ways for this steers to get killed by wolves (for example by having them graze on public lands next to a den of wolves).

What incentive would a rancher ever have for preventing the wolves from killing the steers? If the wolves don't kill a steer, well then there's the hassle of taking it to market and getting market price. If the wolves kill the steer, then they get market price plus 5%, and don't have to even find a buyer.