In monster hunter world at least, captured creatures could be seen back at the main camp and were studied by the researchers there. They could optionally be fought in the arena, otherwise they’d be released back into the wild, at least that’s what I choose to believe.

This was the kulu-ya-ku for me. It’s just a docile, goofy, egg-stealing bird that defended itself with rocks when threatened. Why are we killing this thing?? That was one of the only “monsters” I would always capture instead of kill.