These are in-game purchases, when you spend money on a closed box, and take a chance on what you end up with.
It is against the law for children to gamble, yet these in-game purchases are gambles, and gambling alters the brain, and addiction is a very real possibility as children's brains acclimatise to gambling from such a young age.
They become addicted to the thrill of exchanging money for a probability
These are very harmful. Please dont let your child get ensnared by these - they are even in games such as Fifa, and in games marketed as suitable for children as young as 4.
I dont know why these are not illegal for children. They should be