A step worse too: they are being trained that being bombarded with adverts is acceptable. Genuinely heard (couldn't avoid hearing, the voices were fairly loud) on a train the other week a dad explaining to his charge how he should “watch the adverts all the way through because he'd get an extra coin to spend in the game” and that if he went to a particular screen he could find more adverts to watch. No idea what game it was he was playing.
Pay-to-win is winning, and people are encouraging kids to pay by opening themselves to a little light brainwashing.
[Not a parent myself, intending to never be, before anyone weights in with “you don't know how hard it can be to keep a child entertained”: I know full well, and it is one of the many reasons I'm planning to stay childless, my position on this is an informed one!]