There is some relevant precedent in Dutch courts over this. If you have a fine clause for spamming, and you provide the terms of conditions in a proper manner, both can be enforced by a judge.

In one case ("zaaknummer 676425") a community website got awarded 5000Euro in penalties (500Euro for every private spam message, up to maximum of 5000Euro). The website had put a penalty clause for spamming in their terms of conditions, and continued use of the service meant agreeing to their conditions.

With law it is about intent too. If you try tricks like a proof-reading service, a judge may frown on that or find it silly. But if you send back your terms of service stating: "I charge a freelance administrative fee of 50Euro for reading, evaluating, and storing commercial communication that is send to this e-mail address without explicit opt-in permission. Unsolicited e-mail can be send to this alternative address." and yet they continue, it could stand up in Dutch court (and may earn them a bigger fine for breaking Telecom laws).