It is my understanding that many Muslims are as deeply into their religion (or maybe even more so) as the most serious or radical of the American Fundamentalist Christians are into theirs. Therefore, these Muslims cannot tolerate even one iota of humor in connection with anything religious, while most Americans tolerate and even enjoy the occasional joke in reference to religion, like this one from JumboJoke.com:

Jesus saw a crowd chasing down a woman to stone her and approached them. "What’s going on here, anyway?" He asked.
"This woman was found committing adultery and the law says we should stone her!" one of the crowd responded.
"Wait," yelled Jesus, "Let he who is without sin cast the first stone."
Suddenly, a stone was thrown from out of the sky, and knocked the woman on the side of her head.
"Aw, c’mon, Dad!" Jesus cried, "I’m trying to make a point here!"