It's not only kids that buy these.
I know a lot of 40+ year old men that buy skins and useless junk in video games all the time.
They spend a ton of money on cosmetic junk in short lived video games.
It's puzzling to me, but i see it all the time.
I'm a 40+ year old man who buys cosmetics for CS2 (which has a resale market). If you are going to spend 200+ hours doing something you might as well have a nice environment to do it in.
There's a reason everyone isn't driving a Honda Civic.
Yeah, I'll admit I have and Probbaly will "whale" in my share of mobile games. Though "whaling" amounts can vary vastly on the perception (I'm not throwing down $1000 every time a new character releases. But I do spend triple digits a month).
Key is proper financial management. If I make $10000 post tax (which isnt an impressive figure for a community like this), put 15% in savings, 30% in rent/utilities, and 5% into food, I still have $5000 left. Spending $500 on games won't really phase me.
I 100% agree this isn't something kids would do and balance, though. And I recognize others have addictions and much worse financial planning.