Private libraries (mine for example) are not free, as in beer or otherwise.
Furthermore, public libraries are not necessarily free. In America they virtually are all; fees only for late returns. But this is not globally true; in some parts of the world, libraries open to the public charge a fee for checking out books, or even require a fee for entry.
People tend to call their personal library a "book collection" or the like, but it's a library, in just the same way that a Little Free Library is.
So most people who read have at least a small private library, whether they think of it in those terms or not.
It's a literal translation of "neighbourhood library", it alliterates, and it sounds cute. (Keep the "beep" part short for that).
Good luck getting a jury to enforce the trademark.
(The name is a little weird, because regular libraries are also free...)