I think it would be hilarious and awesome if there was a "Keep Ur Green" quest that required you to pick up an annoying-yet-possible number of the paper water cups--maybe 100?--and gave you favor points with a god (probably Spriggan) as a result when you gave them as a "donation" to the correct god, or perhaps there could be a "recycling" mechanic where they were used as fertilizer (for paper trees?)
You shouldn't get many favor points--after all, a good deed ought to be its own reward, right, Glitches? ;) But maybe you could get 50 favor points for 100 cups.