Critically, Valve allows you to trade items. This results in a couple of downstream effects:
1. Items have real-world value because they can be traded for money outside of Steam. Multiple sites exist for people to convert items into real-world money (certain rare items have been sold for >$1m [0]).
2. As these items have value, they can serve as a surrogate for money in casinos, or for sports betting.
3. This can even lead to money laundering [1].
As such, skins should be considered money, but the sites running these services don't. Therefore, it is trivial for a child to walk into a game store, buy Steam credit, use that credit to buy skins, and then spend that money on literal gambling (as very few sites have KYC). I know because I've actively partaken in it as a child. Even cryptocurrency is harder: most legitimate exchanges attempt to do identity validation.
Some video resources that might be useful:
- Coffeezilla: https://www.youtube.com/watch?v=13eiDhuvM6Y
- People Make Games: https://www.youtube.com/watch?v=eMmNy11Mn7g
[0]: https://www.ign.com/articles/counter-strike-skin-sells-for-o...