No one said that it is the "right" thing to do, they seem to be saying it is the smart thing to do. Maybe some might think it is right if they have a family and can't afford a lawsuit.

It is the expected behavior when the government does not enforce the law equally. That creates perverse incentives for people to either break laws or do things that they would never do otherwise. If the laws were simpler, if the news didn't promote and sensationalize every "miscarriage of justice", then people would not be afraid to do the right thing.

The thing is, we are talking about Common Law countries here mostly with pretty predicatable legal systems. In many other societies where people cannot trust their government to be fair at all imagine how much worse it is, and how much more "selfishly" people act out of fear.