I like the idea of weapons with guaranteed greed talents opposed to it being in the general talent pool. If it were to be added, I think it would be best to make it the only talent on the gun, and have the stats be highend tier (although I dont know where it should drop from)
The only thing that I dislike about it is that you already get rewarded for getting kills. From what I remember, you normally have a 1 in 3 chance on obtaining an item, but for every 2 kills you get as a t and every 1 kill as an innocent/detective, you get another roll of the 1 in 3 chance to obtain an item. Adding a talent that straight up just gives you money on TOP of that is a bit much imo.