Why do cartoons and other American shows never change openings?

[Words Of Wisdom]

Soriku said:

If anybody's watched any cartoons or other American shows (like Sesame Street, etc.) that use openings, they never change them. Most animes always change, but why never cartoons and such?

Just something I've always been thinking of.

Because it's classy.  You're not going to remember that random J-Pop song in 10 years, but this?

Hell yeah.