How can a forum with say 1k or 2k post have 20 000+ members? I see this on just about every forum I visit, who are they kidding do they honestly believe if ppl see so many members then the forum most be good. I understand with new forums you need to make it look active but seriously there is such a thing as overkill to the point of being ridiculous.
If you were the owner would you not try to rectify this problem, when I see this I just shrug and move on.
yah - spammers/bots, and/or the owner going overboard trying to make the forum look bigger than it is.. I always immediately delete accounts with bad email addresses, etc, and also purge inactive accounts over a several months old..
This is common on site like warez where people just signup to view links or download content and they have no interest in actually participating in the community.