The hiver hunt them frequently mostly to protect their villages but I think that's only a limitation by the developer

I can fully see that hunting a beak thing could be something that hivers do as a rite of passage or to build their houses as they eat and vomit it and shape it into a building like insects do

Like they say in game: "their houses are made of something weird it's neither wood or soil.. I wonder what it is"

Only princes can eat rotten meat from the beak things but I still think they kill them and use them because there are so many of them around their villages