From my experience, commercials avoid that sort of policing because they don't want to be labeled by their peers as a whistle blower, not because they're all in it together. They don't want to get corked repeatedly by friends of the guys they report.

Like I said, that's my experience, and I never worked in that fishery. I'm not sure about the regs. you're talking about them violating, but it seems to me that most sport violations that get reported are things that are easily viewed. It's pretty hard to get close enough to another netter to see if he's got the legal mesh size, measure his net, etc.