Whoever implements it, the most obvious one being EA, then just boycott them. I can see almost every company blocking the online portion, the paywall access to the MP to about €14.99 -€19.99 so it would probably make people re-consider buying used. For example, do I pay €49.99 -€54.99 for a new game, or do I pay €34.99-€39.99 on a used game, with no access to online and if I want to go online, it would potentially cost more than buying new.
As long as there is a company doesn't implement an offline DRM (similar to games now, then I see no problem).
Just remembered that EA scrapped online passes so maybe they won't implement their own restrictions.
Either way, the publishers know they'll be fucked if they follow MS's draconian policies.