IANAL, but as I understand it, you don't need to accept a license for software just because it is non-free, patented, or restricted in its redistribution. You need accept a license only if there are restrictions on actual use of the software, i.e. if there is an EULA.
In <https://wiki.ubuntu.com/SoftwareAndUpdatesSettings#drivers> I've suggested how and when EULAs should be presented: "If you are choosing to install any drivers that have end user license agreements, a dialog should appear sequentially for each, with the name of the driver as its title, the EULA in a scrolling text field, the text 'Do you accept the license agreement?', and 'Decline' and 'Accept' buttons". Let me know if you need a more detailed wireframe of that.