It's supposed to sell Windows licenses.

True. The point I was trying to make was that Microsoft pays for the development of .net using revenue from other activities. Why can't Oracle do the same?

I don't think it's fair to say that .net is very effective in selling windows licences when mono can run CLR programs on more platforms than java can.

Despite the existence of mono, the vast majority of .net code runs on Windows machines.

Except Windows is crapware.