Crate training is pretty normal and not sure why you feel so weird about it. Is it “the way of the wild” to keep the dog in your house?
As far as that goes, there's nothing wrong with that and that's not the part that people actually have problems with (but it's a nice strawman to argue against).
The part that is cruel and abusive is locking them up when nobody is at home so they can't damage your possessions. If there is some emergency like a fire, intruder, something falling down, etc, they can't do anything about it.