Very sticky situation.

I think first, I'd "talk" to said person, I say talk and not confront. If said activity continued, they wouldn't exactly be a friend and it would be easier to teach them a lesson.

If we are not part of the solution, we are part of the problem.

Why is said person better than you? You conform to game laws, hunt under the guidelines of your laws and said person doesn't? Is that fair to you or any other sportsperson?

Sticky situation.