Social behaviour, or lack thereof

I was at the supermarket the other day, and someone had just stopped their car in the main road through the car park, and was blocking half the road. The driver didn't seem to care at all that they were causing chaos, with other cars having to manoeuvre around them in a confined space, against oncoming traffic. As I saw this, I had to ask myself: "How could someone possibly be so antisocial? It would almost no extra effort to park, but this person just does not seem to care about the effects on their behaviour on other people."

There are plenty of situations where a minimal amount of consideration for other people, and personal responsibility would make like so much more pleasant for everyone in society. Here are just a few: Throwing your rubbish in the bin, not on the pathway. Letting other cars through in traffic. Turning your mobile phone off in the cinema. Not stealing your neighbour's newspaper delivery. Not playing loud music at 2 AM on Sunday morning. Not blocking the narrow pathway of a crowded street. Flushing a public toilet after you use it. Cleaning up after your dog when it defecates in a public park. Throwing your cigarette butts into the bin rather than out of your car window.

These are very simple things, that take minimal effort or thought, and they make life better for everybody in society - and yet, they often don't happen. Why?

• Theory 1: People are social in small groups (small towns, family groups), where they know everybody and where they will repeatedly encounter them (i.e. they have a reputation), but can be quite antisocial in a larger groups (such as modern cities) where they are anonymous and are unlikely to see the same person again.
• Theory 2: Broken window theory. One person gets away with it, so I should be able to as well - cue a race to the bottom.

Postscript: Lynn Truss covers this topic in her book in far greater detail than I ever could.