Not everyone works alone
I'll tell you why...
Even if I use OpenOffice myself, I cannot force everyone with whom I share office documents to do so. So, if I want coworkers, board members, grandma, uncle bob and whoever to be able to open, read and edit the ODF documents I create, I need to tell some of them to install the ODF plug-in. (Which is less intrusive for them than to uninstall MS Office and install OpenOffice.)
Biting the hand that feeds IT
