As long as we are discussing this lets dig a bit deeper:
Lets assume that you have these rights. So after a year or two of hunting "ethically" your wife suddenly loses her job. Its the start of a long winter and as a construction worker you prospects of work over the winter are slim. You're a proud man and accepting welfare is out of the question. There is a herd of animals that winter close to you. Are you going to remain ethical, and let your family suffer? Or say you know of a man who will pay top dollar for trophy horns. What are you likely to do? Its an awful temptation. So you justify selling one set of horns. Then school starts. Your wife hasn't found a new job. Your kids don't have new clothes or shoes. What are you going to do? Heck, whats one more set of horns? Heck, its better than your kids doing without. Now lets say that your oldest is accepted to college. He/she has a chance at a better life than you ever had. But, you can't afford to pay for college. What to do?

I know these are all grave examples. But, none are out of the realm of possibilities. Food for thought.