Highway litterbugs do so because they want to get rid of their trash instantly, instead of keeping it in the car until they reach their destination. As a result, there's a fairly evenly distributed coating of litter all along the freeway, looking ugly and requiring long cleanup time.
If there were designated "trash areas" (shoulders where you could slow down and toss your trash out the window, then rejoin traffic), then people would be willing to hold their garbage until the next trash area.
Cleaning equipment would be right there all the time, so the cleanup would be a lot easier with litter all in one place. Occasional global cleanups could still be done.
Suggested sign: "Throw-N-Go, 1/2 mile ahead."
Another idea: Give Your Trash To The Toll Booth Clerk.-- phundug, Aug 13 2006 Baked - this is called the Bronx.
Highway rest stops already provide waste bins. This just encourages the worst kind of litter bugs.-- DrCurry, Aug 13 2006 I think it's something usually done without much consideration, so providing areas for it wouldn't work. Anyone likely to be aware enough of what they're doing to wait until there was a designated area would also be prepared to take their trash home or dump it somewhere appropriate. Toll booths are not a good place because it would create longer queues or require there to be more booths.In any case, you're still talking about a large, probably windy, area strewn with litter.-- nineteenthly, Aug 13 2006 random, halfbakery