[fortran77]

If he painted something without permission on someone else's wall (for example), I don't have a problem with the owner of the wall trying to profit from it.

And if he painted something without permission on a wall owned by a Government, funded by "The People", I don't have a problem with anyone trying to profit from it via photographic reproduction (modulo local copyright / ownership laws of the country the wall is in).

Warhol made art from someone else's Campbell Soup cans and everyone loved that....

[bufferoverflow]

Warhol's art is transformative, so there's no copyright issue. Straight photographs of art are generally not considered transformative by courts.