The fact that the stateside dance scene is still growing, in addition to corporate interests plowing money into the still "emerging market," means that festivals in America get better every year. They're booked better, they're run better, and there's new competition every year driving things forward.
In the UK, this whole festival culture thing has been so played out that festival brands don't really give a shit anymore about the experience. They'll know you'll keep coming. This is because the British don't actually care about fun, they just want a place to go and roll around in mud and trash, maybe get stabbed, and check out some piano house to wax patriotic over while knocking themselves out on nitrous oxide.