I love this feature in hatchery but i feel like it would be so so so good in stables too. I have 2,484 release pets on my account atm so if i could mass release a whole stable... that would be great xD

Yes, yes yes yes yes yes. I would absolutely love this, it would make stable cleanouts so much easier

Could be a really nice thing and im sure many others would like that too.

yes

Yes,

and why players release pets?

there are a couple of places on the site where releasing pets is a mechanic of the game that gives a bonus.

during the Spring Festival and the Patriotic Event, there is a contest where players can receive prizes based on how many pets they release.

throughout the year, you get an encounter bonus based on pets you release that are 42 days or older in the Lost Grove section of the map.

there are people who use it to temporarily freeze their pets too, since if you release a pet it isn't deleted - it's just frozen until you call it back. i've seen people use this for projects when they are waiting for more appropriate times to nurture boost pets.

there's also the base use: people get rid of pets they just don't want so they don't clog up the sales on the site or their stables.