If there were any under cover cops, They did a terrible job. People where walking around the camp site yelling stuff like "Hash! Molly! Opium!" I mean, Who the fuck smokes opium at a music festival. you could pretty much do whatever after you got through the check point and its fine. If your buying, They don't care. If you are selling, They probably don't care, but its less safe. They don't want to have to kick you out because getting any of those cars out of the lot is pretty much impossible. I saw two people getting removed entirely from bonnaroo the whole time i was there. They must have done something real bad. There where lots of girls with "I need molly" painted on their bodies and stuff. You can get away with almost anything there. TL;DR you should be more worried about buying fake drugs then Undercovers.