@MoiraGoggin is absolutely correct, and that version of the EULA pertains to any version of the software, including those on 3.50 or 3.71 or 4.05 not on maintenance. It would not be worth Sage's time or expense, but they could legally go after all those users.
An interesting comment from the BPAC meeting, I believe it may have been Connie Certusi, was that there are a number of companies who are not paying to use the software. I fully support whatever Sage needs to do to stop that, because we lose also.