Is paper junk mail still that much of a problem? I hardly receive any (but I've got one of those stickers saying I don't want it), and assumed it had died due to the rise of online advertising.
Translation:
NO unaddressed printed advertising material, door-to-door news papers NO
These stickers are reasonably well respected here, and violating them leads to a barrage of complaints to the advertising company. Lots of people have them.