Good on em!!! unfortunately it wouldn't surprise me in the least if they got busted by authorities for their efforts its a silly world we live in...
KiM
EDIT: i thought then, this would be a good job for these pricks that graffiti public property with their tags and shit spray art, when they get busted get them on the freakin roads re-painting them rather than doing community service picking up trash on the side of the highway, leave that to those with 'less' artistic talent...Again though good on these guys, saving the Government $$$ doing it at night when there is less traffic so not to disrupt traffic or endanger themselves their actions could be responsible for SAVING other cyclists lives! and they did a pretty good job too!