I don't think it's legal to take some kind of "taxes" by pushing ppl to buy official game.
"Only licensed software can be used to access online services, download content and apply updates and patches. If the Software permits access to additional online features, content and/or services, only one user account may be able to access those features at one time."
I think more than enough was said here. Game now offers FREE connection to WOL / XWIS. You cannot permit some players who validate their copies while own producer leave he's own product to gesture of ppl.
If you want to ban cheaters or un-authoriesed user's You can't demand money from free product (Tiberian Sun). BUT - you may demand for use Your server. The only thing here to think is what is your term with EA. Are You owner of server or just Administrator of it? You may think about how to authories ppl through server by donations or so. It's in Your competence.
So this is my idea:
Move server to area where secondary programs are needed to play online - such as GameSpyArcade or Xfire. It can be changed by un-official patch - coz game is no longer supported.
It can hurt TS community - but also not affect to ppl who don't want to buy game coz they pass it, already.
P.S. My second account was KyouMass, but e-mail is no longer validate, and i don't remember password. I can prove it - but i don't know how