There are Mulitple issues here you are addressing
unyquity, you are addressing more than one issue here. the first issue is the commerical forum issue and the fact that folks should be made TOTALLY aware if they are in a forum ran by someone who also sells products, vs. participating in an information only forum with no profit making involved. i think its obvious to anyone with integrity that a distinction needs to be made, a very CLEAR distinction, much more clear than now exists.
the second issue you address is much stickier and involves bizarre, off the wall, insulting, abusive, and potentially even dangerours advice that a commerical forum owner may post. i mean how can you curtail this?
first off, my personal opinion is that ALL forum owners absolutely should be held to a standard of ethical and respectful treatment of posters. this means no abuse, no insults, no personal attcks, no demeaning and condescending language, etc. i think thats fair. in the past i confronted one specific forum owner about blatant abuse and got stalked all over curezone by his groupies, harangued, harrassed, and in the end realized it was pointless. posters seeking advice have the right to be treated with respect. period, end of story.
then there is the issue of dangerous and just plain weird advice. how can you tell a forum owner what advice he or she can or cannot give? either they get to give the advice they see fit or they don't. you can't tell them "you can say this but can't say that." telling people that vegetables are bad for you is pretty laughable, and maybe even dangerous, but thats his opinion, thats what he believes. what are you going to do, post a disclaimer saying "weird advice dispensed here"? you can't micromanage someone's forum, either you accept them or you reject them. its an all or nothing situation, unless of course they start telling poeple to drink draino or something.
thats how i view it anyway.