Stealing something illegal

Okay so check this out, turns out that people are starting to rip off Graffiti and the morality compass on this is going haywire. Not that major corporations ripping off ideas is anything new, but something is definatley wrong with this picture. Here's a sum up as to how I see the morality of this thing; someone puts a graffiti piece on a wall, which is illegal, but since it is still documented the Graffitist in question can be said to have ownership of the idea; Then someone comes along, and steals a illegal piece of art, puts it on a T-shirt and makes money off of a stolen idea.

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SCREW IT! I can't find any real way the morality goes here. Despite the ambiguous morality of the entire situation, yet I think it says someting about today's world when well respected companies are nicking and biting other people's work. Moreover for that matter, illegal art, so if someone wanted to bring them to court about it; the Grafittist would be arrested well the Fat Cat would walk free, since the Graffitti was illegal to begin with and probably wasn't protected by any such bull termonology like "intellectual property" or "copyright laws."

Dammit.