Yea it's a little silly. Overtime I think some of those groups become echo chambers, basically they drive away anyone with a different opinion. I like to encourage people to get their information from multiple sources, so of course read what we say here, but check out other forums, care guides, etc etc. I think what happens with groups like you found are those guys show up there, get some advice, and never look anywhere else. So to them, there's one way to keep a BP and if you do it some other way you're neglecting your animals.
Silly but I get how it happens.