I always go against the idea of banning scammers, as that ruins any feeble chances of a refund that might exist.
About a section like you mentioned, its feasible, yes, with a good amount of customization of vB(something KWWH admins won't want to do), but not desirable at all.
But yeah, a separate section for discussing scam reports would always be a good thing, at least the pretty General discussions section will be spared of these shit drama threads.