It really isn’t cultural. In the early 1900s, William Kellogg (of Kellogg’s) was a puritanical Christian. He hated the idea of masturbation more than anything, so he created Corn Flakes to be a cereal so bland it would kill your libido and prevent you from masturbating. He also was a proponent of circumcision as a means of preventing masturbation because it would make the penis too tight that stroking it would be painful. Americans bought into his propaganda that circumcised penises are “cleaner” and then it just became “well, I’m circumcised, and my son’s penis should look like mine!”
No one said that the average American was intelligent.