I wouldn't be too quick to assume everyone knows/knew about both sites.
Considering there are a few folks who think they've been banned here, there has obviously been some confusion about the registration process here (it took me two days to get it right). If they think they've been banned, they at least tried to register, and probably got derailed with the "fill in the date" screen (that's where I had a problem--didn't know I was supposed to enter my birth date). Those who think they've been banned now feel slighted, and in some cases, angry. That is misdirected anger in my opinion.
Bob