The evolutionary base for littering.

I kneel to no man when it comes to my hatred of littering. From my window I can see a well littered area and watch as cars draw up at traffic lights and throw things out of the window. The problem is that littering seems to be universal barely contained, from our first step onward we seem likely to discard things at the first possible opportunity.
The obvious motivation is simply to get rid of something which we no longer need and which can be of no further use and which carrying around will use energy and prevent us from picking up something else. However, it isn't to our advantage to discard things in the immediate vicinity of our home, discarded food may attract predators or act as a reserve for bacteria or other pathogens.
There may be some positive benefits for certain elements of untidiness. It is often noted that other creatures distribute the seed of plants in their faeces, humans would do the same and additionally when discarding part eat fruit, off the foraging tracks, we sow the seeds of future food sources within easy reach of existing tracks, possibly the beginnings of gardening.
If littering is a deeply ingrained, evolutionary tested strategy, the fact that it has become inconvenient is going to be difficult to deal with. It does make the problem of dealing with littering considerably more difficult to deal with than just some lately acquired habit.
The strategy has become dangerous and counterproductive for several reasons, the density at which we live, the removal of wild animals at first caused problems as the removal of the rest of the ecosystem made their life impossible, then as our levels of waste became higher, the animals that came back in great numbers as they were able to live on our waste.
The only way to truly counter litter is to trigger the instincts that prevented us from littering around our owns homes and expand that area, your guess how to do that is as good as mine.