Yes, the domains in the restricted zone is added by the immunize, the Hosts file does not do that, it redirects a domain to your own PC, hence it becomes unavailable altogether.
In fact the way the restriction is done is not correct. There is a *Dword =4 in adelphia.net key in the domains key, that makes the two subkeys Users and www redundant (all *.aldelphia.net sites are restricted by that DWord). If the idea was only to restrict www.adelphia.net and users.adelphia.net, then there should be no *DWord in adelphia.net key, only the ones in www and users keys.
I've noticed a lot of the restricted domain entries from Spybot have the same error. Maybe someone should review these immunize entries.