I see absolutely no problem with it. You have your management standards in place and everyone who hunts with you should follow them.

I have a 130" minimum up here at my camp and a $100 fine if they shoot one under. The fine isnt meant to be a big deterrent, its just to make a point. The guys who hunt with me know that I have a waiting list 6 miles long and if they don't want to follow my rules, someone else can take their place that will.