Scott,
I've actually produced some 4' x 8' images of graffiti art from photos supplied by a customer. Never worked on walls because I never did what you would call Graffiti. The only walls I ever worked on had advertising or lettering and I was paid for it.
Here's one example done ages ago.
Anyway, having never worked with graffiti paint aerosol cans before, it was interesting that the local supplier had the stuff locked up!
Locked up because it was quite common, so they said, that the graffiti artists who purchased the products, made attempts to get them for free.
Now, you may say, so what? And that's understandable. But in all the years I've been frequenting artist supply houses, well over 40, I've never seen any art products locked up in screen enclosers.
Graffiti artists, go figure!
Thanks for this Thread and that source, you've got me thinking!
Charles