In Denmark, you pay a little extra for the bottle itself when you buy a soda, you get that money back when you return the bottle to the store for recycling. This provides a nice enough incentive for people to generally not throw bottles, and it provides an nice extra income for kids and others who collect the bottles that do get tossed. I bought my first ethernet card with money spent collecting bottles at a concert (I hauled 4 large trash bags, worth about $100 in a single evening).

I don't get why this is not how everybody does it.