I'd be a lot more impressed if large companies were NOT allowed to trade carbon credits, surely that defeats the object
Yes, it does seem a bit of a cop-out. The attitude that "I can't be arsed to reduce my carbon footprint so I'll pay you to reduce yours" is pants, really.
Still, I suppose it's better than "I can't be arsed to reduce my carbon footprint and I don't see why I should make any financial contribution towards anyone else doing it either"