I know it's a long hot weekend and it's easy to get carried away with the summer atmosphere, but believe me, you don't want to wear flip-flops to a festival. If you do, you're just asking for a rather large and over-enthusiastic fan jumping on your little toe right in the middle of Nick Cave. If you manage to make it through that ordeal you'll have to traipse through the indescribable liquid festering around your nearest portaloo. It smells unmentionable and by the third day of the festival it'll be an inch deep (or in footwear terms, 1.5 flip-flops). Trust me, that's the last thing you want to feel between your toes when you're miles/days away from a hot shower!
Is this your business?