It might seem illogical for people to be spending so much money on Pokémon cards, etc., but for younger collectors (some of whom are Bitcoin millionaires, Tesla millionaires, etc.), those cards were part of their childhood, and comic books weren't.
There's a reason why the money people are shifting out of comic books and into video games and trading cards. Comic books are close to their zenith, whereas Pokémon cards and Nintendo games are on their way up. It's a matter of demographics. I don't begrudge Millennials their hobbies.