Until property taxes eventually push them out as it has done in some urban communities. Ownership is huge but prices will always rise so I think it's hard to ever let their guard down.
Property taxes will eventually get you, but if the bookstore owns the building its in, it will (almost by definition) be able to sell for millions and move elsewhere, if it wants to.
Usually (in my experience) it survives until the owner retires or dies, and then disappears.
