While you may consider crating a dog to be cruel, I know many dogs that have ended up in shelters that could have avoided the trip if they had been crate trained.
Same. I keep saying to myself, when I see certain dogs at the shelter "this could have been prevented with crate training . . . "
I crate trained my dogs and don't regret it. They love their crates and I leave the gates open so they can come in them at will. I only shut them in it if if I'm away and can't supervise them.