Sure you do! Shepard Fairey is that guy that traced that annoying agitprop of Obama that everybody copied, back when it was about the only socially acceptable way to make fun of the President. Oops! Did I just type that out? My bad.
Anyway, if you want to see what happens when Fairey covered over an existing mural in NYC to put up what appears to be a distinctly inferior mural of his own*, click this link. Fair warning: some of the pictures are probably not safe for work, as they involve the unauthorized addition of the fanciful depiction of male genitalia to the main work. But in an artistically relevant sense!
…Actually, yes, it was. This is a very interesting photo-post of street art (kudos to the blogger who did it), and there’s one picture in the middle that Fairey should have looked at, screamed “YES! THIS IS PERFECT!” – and then put up an armed guard to keep the taggers away until he could get the whole thing covered in lucite**. Click on the link here to see it, after you view the whole thing.
*Personal opinion, but one apparently shared by a nontrivial proportion of the NYC street art community. Nice to see some common ground there.
**If, you know, he was an artist or something.