Since I myself sell gift cards, I wouldn't agree with banning the sale of git cards on the forum. However, there are some obvious users who trade illegal gift cards as well as keys that are bought from stolen credit cards and they sell it at 20-25% face value. I would like that it should stop but still there is no way to prove they are illegit unless the websites are contacted and informed about the same. Also, there are many members who buy these illegally obtained gift cards. Don't get what they get out of it.
I don't agree that it will hurt bitcoins as mainly CC's are used for the purchase of these gift cards and not bitcoins. Don't get what's hurting bitcoins in all this.