Due to the ridiculous nature of loot boxes in many recently released titles, some fans have asked the ESRB to do something about it. Namely, to classify loot boxes as gambling. Unfortunately, that doesn't seem like it is going to happen. Here is what a representative had to say when asked:
“ESRB does not consider loot boxes to be gambling. While there’s an element of chance in these mechanics, the player is always guaranteed to receive in-game content (even if the player unfortunately receives something they don’t want). We think of it as a similar principle to collectible card games: Sometimes you’ll open a pack and get a brand new holographic card you’ve had your eye on for a while. But other times you’ll end up with a pack of cards you already have.”
While calling them gambling may not be the solution, something needs to happen. Loot boxes in single player games are unacceptable, and shouldn't even be an option for developers going forward.