Pokémon seem to take on the values and ideals of their trainers. I'm not sure if it's the pokéball technology that changes them or if pokémon are naturally blank slates that need trainers to fill them with ambition.
Natural or unnatural; I'd argue they're still friends. It's probably better than messing about in the wilderness anyway.

I've seen like 1% of pokémon so let me know if any of the other 99% contradicts this.