Yes, like their own religion. Should that be banned because some see the Baha'i faith itself to be dangerous to society? I think they have experienced that historically already, so it's curious having suffered that themselves, that they would want to do that to others.Before arguing that things you disapprove of should be banned (edit: or that their sale should be prohibited), maybe ask yourself if there's anything you value that others may disapprove of.
Make you wonder. Aren't they just wanting to do to others, the bad things that have been done to them? That's not healing. That's just perpetuating the violence and injustice. Bullies make bullies, I suppose. I think the golden rule should apply instead, "Do unto other what you have them do unto you." Do they want others to ban them? Then don't suggest banning choices for others.