>>723119640 (OP)
It produces the illusion of value at a substantially lower cost than actual investment and speculation. Other than people who get skins because they play the game regularly and like the customization, a large number of them can fixate on the possibility of return and feel accomplished and clever. So long as the marketplace exists, it's going to be valuable some day don't you know?
I got an M4A1-S Basalisk back when I played because I thought the engraving was neat and it was my favorite weapon CT sided. I sold it for a game maybe 8 years ago. I don't even remember what game.
The short version is: It's just like the ape jpgs. Novelty and speculation produces a unique dopamine response.