If that creature loses all its abilities, it will still be exiled at the beginning of the end step, and if it would leave the battlefield, it is still exiled instead
Commander 2019s Merciless Rage uses the madness mechanic a lot, and it turns out that cards cast with madness are technically cast from exile
The Beamtown Bullies is also a different effect, as it animates your dead creatures, not the cards you have in play
You can also fire it off for lower amounts and just draw a ton of cards yourself, or combine it with Laboratory Maniac and a load of mana for a cheesy mathematical auto-win
Outside of Megatog and Atogatog, the most an Atog costs is three mana, which is pretty compelling
Most of your deck is artifacts and you obviously want them around forever