I have used OpenOffice and LibreOffice since forever.
The question I have is "why is it free?"
Occasionally I have made a contribution to the the "make a contribution" place -- where does that go? Is it good to contribute to the LibreOffice foundation?
Who (aside from the users) benefits from having a free alternative to Office? In most respects it actually is an improvement over the Office program.
I really got mad and vowed never to use MS Office ever again when I upgraded to Windows 8 and my MS Office suddenly became inoperative -- the license wouldn't transfer, even on the same machine.