I suppose if some people don't hunt public areas, they have nothing to lose if they're closed to metal detecting. I at least would like to keep the option open. Even though I've hunted just about every park in my area several (if not dozens) of times, they never seem to be hunted out. You return after a rain or a change in conditions, and/or bring a different machine, and place can come alive again. Just try to do it without drawing attention to yourself. Even if they had signs saying "Metal Detecting Welcome!", that doesn't mean you can do what you want, or, that someone couldn't complain for any number of unrelated reasons. I prefer to be the invisible man.