As far as people who never listen, and are cheap, be aware that we cannot just ban the Serpa: there are knockoffs of the principle as well. I have actually seen people with these, and cannot get them to stop using them.
Love how the illustration for one of the Zahals even shows you trying to shoot yourself. Requires tip-of-finger use:
Luckily, they don't draw pistols around me, nor do I rely on them for my safety. But
I banned them too