I am invited. No you shouldn't accept. The Poon Squad are a better clan to be in than the DARKLORDS. The Poon Squad have a thriving community and regular clan games and tournaments, despite their questionable tastes in settings, and their low reputation.
Yes, they invite everyone. This latest one has to be my fifth invite. My favorite was when I joined, harassed them on their forums, was kicked out and then immediately invited to join once more
They literally invite everyone. If you have clan manager rights, spam invites at them. If you don't, send Darklordio about 100 mails asking him to join a your clan.