I'd find it fair for these games to be classified only for adults.

As for adults however, my philosophy is that we should stop treating them as kids that need to be told what they are and aren't allowed to do. Loot boxes are addictive? So is sugar, alcohol, sex and 1000 other things. Do we want to go down that road?

If someone wants to gamble a percentage of his income, that should be his choice. If he wants to gamble away all his money or even put himself into debt, also his choice.