Read this piece of trivia in foaming mouth guy:
"There were originally plans to have a "foaming mouth girl" at the Revelation rally, however, this plan was scrapped as the creators felt it undermined the creepiness of the event."
The essential difference between LOK and ATLA is the refusal to self-critique, like this instance. A foaming mouth girl would have underscored the ridiculousness of Revelation rally. The foaming mouth guy is a self imposed limit on the part of the creators that lets one know when things have gone too far, or have not gone far enough.