It is an interesting concept. But, why would anyone want to listen to the same music everywhere they went?
Also- In case nobody noticed, most of the music at burningman is already synchronized-- about 90% of the "dj's" are all playing the same top 100 beatport tracks that they just downloaded 2 days before arriving at the playa. So no matter what camp you walk to, you get to hear the same tracks you just heard 10 minutes ago. Then, you get to hear them again the next day because the new dj's only have those same songs...then, the next day, then the next day, until you have a headache because you can name every song you hear because you heard it 10 times.
Also, if anyone decided they were going to use RF freqencies to do this, you would have to watch out for assholes like me who would find out what frequency was being used and jam everyones receiver with more powerful transmitter just because I could.
Purveyor of Fine 'Soul Crushing Bass'