There's a big fence around Glastonbury - and wandering off into the Somerset countryside doesn't hold the same level of risk as walking out into the desert...
And while never having been to Glastonbury, I strongly doubt I'd have the opportunity there to get as close to the action with things like Greg Leyh's 30foot tall Tesla Coil(1), or Jim Masons flamethrowers(2), or Dance Dance Immolation(3), or even the somewhat more "safe" artworks like Crude Awakening(4).
I know Burningman has a _very_ strong "hipster douchbag" reputation these days (and I won't argue that it's not at least somewhat deserved) - there is definitely something more than that as well.
