When I opened a rare key, People can get a disguise , But its annoying when you get one and you already have one, so instead, we could get a rare key back when we get a disguise.
As Benny said, this suggestion has already been created and I most definitely prefer the other suggestion, sorry.
Even if there was no other thread about this, no support because the keys arent always meant to be beneficial. its a gamble.
No support, as others stated it's gambling and once you gamble it's hit or miss (no pun intended ) However, you can offer a different disguise or something less or equal value to the disguise.