In regards to your hobby comment, yes....we do discriminate based on the majority of behaviors witnessed in this area. Fishermen are not permitted to fish on our land either. Why? They leave trash everywhere. If folks were adult enough to pick up after themselves, we'd be more than willing to share the water.
My husband and I are do not object to outdoor sports, including trapping, hunting, fishing, bow hunting, muzzleloading, target shooting...any of it. In fact, we own a small fly fishing shop. What we do have difficulty with is irresponsible behavior on the part of many who endanger others and leave their trash behind, ruining natural environments.