The mods have no capacity to stop it. The site runner has to do something. All we can do is flag the spammers, which hides the spam and blocks the source. . But as fast as we do that, they morph and flood us with more. You haven't even seen how much we've gotten, as I usually hide it in the wee hours when I'm the only one awake.
We had the same problem on the MKZ Forum. It's been fixed, but not by the Moderators.