Microsoft and other big companies are literally getting the stuff for zero dollars. That they choose to contribute is because it is in their best interest to d

Microsoft and other big companies are literally getting the stuff for zero dollars. That they choose to contribute is because it is in their best interest to do so. Free software is sort of a brain hack in that way: because Linux is successful, it is in Microsoft's best interest to contribute. But that's very different than saying, for example, that Microsoft owes dues and pays them.