Hedge funds generally strip & kill their victims, but I hope that's not what happens in this case.
I'm not sure that's true.
Hedge funds need to be profitable, or they cease to perform their function.
If they take over a failing business then yes, they'll do what they have to do to make it work. And that can include selling off part of the business, or changing its direction so that it can do better. But if they take over a robust business they're going to want it to continue to perform, as that's in their interests.
I don't know how badly or how well B&N is doing now, and I'm not necessarily in favour or against this buyout: but after some shaky years Waterstones is doing well under their ownership, from what I've seen, so we could hope that B&N enjoys the same success.