I live in a place with sensible firearms laws, so this is totally a thing. Gun owners are licensed, and part of that license is a “good character” and “legitimate purpose” check. Self defence isn’t a legitimate purpose, so if you start running your mouth on Facebook about shooting people on your property there is a tip line people can send reports to, and you can expect a visit from the local police. Similarly, getting caught DUI will violate the good character requirement and you’ll need to surrender your guns - you’d better be able to account for all of the guns registered in your name or you’ll end up with a much more serious conviction