Little Boy Humor isn't funny to Mom's

At what point does the gross kid in school stop being funny? Seriously? When do we all collectively realize that what they are doing is gross, and that we should stop laughing and encouraging them? Yesterday, Marissa, Ethan and Karoline (a neighbor) came in from playing outside. They were all giggling. When I asked what was so funny, they all broke down laughing and told me Gavin had just peed and pooped outside in the yard. Well, apparently ages 4,5,7, and 10 years old still find this kind of thing quite humorous; unfortunatley, their Mother does not!