>>47400679Because it's a video game. They were originally bands your Pokemon wore, then FRLG made them DVDs that you watch on your Teachy TV. And Pokemon GO, they're scrolls.
Really, they're just a game mechanic shouldn't be considered an actual part of the universe. The anime made the right move in just having TMs and HMs not exist and having all moves in a Pokemon's movepool be learned by training or "level-up".
