I don't recall The Spectacular Spider-Man using potty humor (or much of it) and it doesn't seem to hamper the shows success.
I'd say the use of it is similar to adult toons being reliant on adult content. Lack of faith in the creative writing.
Plus, considering that A Pup Named Scooby Doo and Tom & Jerry continue airing even without potty humor, it should be an indicator that it's not necessary.
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