Most of the enforcement actions I have heard of were people running pirate broadcast stations, people intentionally interfering with public safety radio traffic, or once in awhile someone causing interference on a ham radio repeater.
I have never seen anything where someone was running excessive power or something like that. Or using non-type accepted radios for FRS or whatever. As was said, they don't really have the time or manpower to investigate things like that.
FWIW: It is fairly common in this area for people to use UV5R radios for EMS or Fire Service applications. They arn't issued by the department, but individual guys who want their own radio and the department doesn't issue them one, buy one themselves and there are guys who have a code plug for them. Obviously this is with departments that are still using analog FM on UHF. I see this as a major safety issue, but I guess if the department doesn't have the money to issue everyone a radio, it might save your life if it works when you need it.