Can someone explain to me why filmmakers feel the need to put scatological humor in kid's movies? It completely alienates the adults!

To tell the truth I don't know why anyone feels the need to put scatological humor in anything at all-- kid or adult, I've never liked it. "Ice Age" was one of the few recent animated movies I've intensely disliked, so I don't plan to see "Robots" (by the same creators I think) at all.