Seems that a fair warning and a 30 second chance to return to home would be sufficient before grounding a drone. I'm not anywhere near a NFZ other than the local hospital's helipad that is 5.7 miles from my house but I think that causing a pilot to lose a drone is a bit harsh if in fact that pilot has been issued a fair warning and given a chance to correct the situation. Maybe if these instances of flying in a NFZ just put the drone in an unalterable RTH mode would be better for everyone. I however am not saying that blatant or accidental flights in a NFZ is acceptable. As it has been pointed out, there are plenty of apps that inform a pilot of the situation BEFORE takeoff. In other words... fly responsibly as well as safe.