^They're already busting down on bars and local
cover bands for playing unlicensed music.
I knew somebody who was part of a non-profit that had a thank-you picnic for their volunteers last summer. It was held on private property and it was by invitation. Somebody attending must have ratted them out to a buddy in the recording industry.
The local organization got a polite "reminder" a few weeks later that any public performance
(which apparently includes playing a CD through a portable stereo system out on your patio) requires some sort of license in order for it to be done legally. The letter suggested that next time they hire a DJ who had already obtained the requisite performance rights
in order to stay on the right side of the law.
The letter wasn't exactly a threat. It was more like a "perhaps you didn't realize you have just broken the law and could be in serious trouble had we decided to pursue it" sort of things. It was probably left at that because this was a recognized charity with some very serious money and political cachet behind it, so they wouldn't have simply rolled over and played dead if it escalated much beyond "a word in your ear."
But it wasn't a joking letter either.