I think he means the keys to open up the cases. The cases have a variety of weapons inside of which (when opening with a bought key) you will get one. The weapon you get can be a very common one (and thus wasting a key) or a very rare, awesome weapon. It's playing russian roulette with your wallet being the victim
Yeah that's exactly what I mean. Well you mostly get bad skins for weapons, already bought yesterday 5 keys and got only bad skins and are 10cents on the steam community market.