I like the idea very much. At last somebody is doing something to raise awareness about too much litter around. When I walked the Ring of Steall the previous weekend, I counted about 10 rotting banana skins dumped all along the path...
I've recently had a bad experience when I politely asked somebody to pick up what they dropped (I wrote about it in another thread). I think educating the young generation is the key and this funny banana-man will certainly attract kid's attention
Good luck!