When I was in uniform, I always made it a point to have a brand new nickel in my pocket.
Anytime I was handling one of society's finest who gave me the "I pay your salary" line, I would just pull out the nickel and offer it to him. He'd say, "What's that?" I would explain to him that about 500,000 other people also paid my salary and when you calculated my salary divided by all 500,000 it came out to his contribution being less than a nickel.
Then I'd tell him (or her) that I no longer worked for him/her, and I would go ahead with whatever necessary action he/she didn't like. And I always offered to let him/her keep the change.
Amazing how many jerks it shut up.