[Mogga]

Originally Posted by affearner To the customers: How will you know that the coupon codes you're using are for real?

For some customers recently they found out using codes off a forum didn't work out very well for them. They'd read that they could combine two vouchers and basically get lots of discount on an online shop. So they did.
The company being abused did what's in its T&C and cancelled the voucher they weren't supposed to use. Result? Lots of very cheesed off bargain hunters who'd been seriously misled by a forum posting.

Companies need to protect themselves. Consumers need to be aware that the super-duper amazing offer sounds too good to be true because it isn't.
Sites need to be responsible and vet the codes their users post.