Ok I'll agree upon it being a shades of grey - kind of thing. But why not just outright ban someone when it's clear he doesn't fall into those categories of a spammer, a scammer or a troll. Would be much more polite and straightforward in a kind situation where you just seem to have the "wrong opinions" that don't fit the forum or whatever.
I agree that it’s not nice to them, which is acceptable most of the time for most people because the ghost banned members are not really nice community members. It is an issue when someone is ghost banned for bad reasons or a bit too fast.