Many of the participants are behaving like animals.
Butterflies
are animals - maybe that explains it?

Does anyone have any great ideas?
You could start by honoring the voice of this community: 1011 people voted so far - and 786 (77.7%) said
Give BFL a scammer tag.
What's more important for you? Money (from Ads) - or your integrity?
Butterflies are not Animalia they are Insecta.
Ideas:
1. Like the two subforums idea for vendors. Those that are 'legit' and those that are 'unproven' or 'untrusted'.
2. Make all vendors post self moderate topics and have a complaints subforum for vendors to respond or ignore and all outright scam accusations still go to scam.
3. Have all vendors use a registered and designated account that can post notices only about their products.