I don't know about that.
http://www.dotaoutpost.com/trade/13415266
This fine gentleman here sold his copies for 8 keys.
hehe true, I havent seen payday 2 @ 8 keys on steamtrades even once (and I am not a seller, not tryin to spread propaganda or anything)
I'll give you an Original rocket launcher on TF2 for 8 Treasure keys, final offer.
Take your time to think it over.
This is irrelevant to the trade and slightly offensive so I'll just ignore it.
Dear Sir or Madam,
I am grossly offended by your choosing to be slightly offended by my previous comment, I do not take kindly to such posits and will be contacting steamtrades to let them know my dissatisfaction.
Yours sincerely,
Theodore Buttwash (Ms.)
He selling copies from giftable 4-pack's, if using exploits okay for you - good luck.
Don't see how it's an exploit if the money reaches Valve/Publisher and you get your copies to do as you please or give to a friend, since I was on his friends list I was technically a friend when he gave it to me.