They don't have the right to ask them to pay for the software, but they have a right to dictate how their trademark can be used. They're free to distribute thei

They don't have the right to ask them to pay for the software, but they have a right to dictate how their trademark can be used. They're free to distribute their software under a different name. They could also deliver an unmodified copy of Ubuntu to their customers, which would allow them to keep using the Ubuntu trademark.