I'd say that even though banning isn't something which is done often on here, we do have a good amount of people who regulate what you're going to be able to do with your account and if you're going to be trusted. As most of the scams in the services, lending, etc (sections) are all painted red by the DT people to ensure that people know that they're not to be trusted.
Action isn't taken on banning too often, this is due to the fact (in my view) that we really don't have enough mods to be policing every section-- though default trust painting the scammers red does pick up a lot of the work for the staff team here. So I don't see the lack of bans as an issue IMO.
The forum policy for dealing with scammers and spammers is different. As you can see yourself, a scammer or potential scammer would be tagged accordingly by DT. But that does not mean they are going to be banned.
In other words Red Trust and Ban are mutually inclusive and not exclusive in all cases. They may be exclusive if both offences of scamming and breaking rules are there.
If you refresh it now, and then you'll soon see that there's hundreds of posts/users being dealt with every hour.
Honestly I am myself often at awe of the huge amount of work the mods are having to do - to nurse the diarrhoea of the forum shitposters who are spamming the threads to get paid.