Hmm. Might it have increased taxe revenue too? Thereby allowing more
bridge maintenance?

Maybe. However I suspect not by much.

How about those bridge maintenance crews didn't
have to spend as much time working around graffitti? Perhaps they took
more pride in their work? Gave that extra 10%?

I doubt it actually.

Made them feel [... t]hat their work wasn't just trashed to no avail by the
next street gang?

Maintanance isn't just paint that gets trashed by a street gang.

Jose
--
There are more ways to skin a cat than there are cats.
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