According to a well-known psychological research (google for it and I'm sure you'll find some links), a subject is given the following two options. (1) The subject earns 500k per year while all his friends and neighbors earn 1M. (2) Subject earns 100k per year while all his friends and neighbors earn 50k. Majority of subjects choose the second options.
This explains in part why people can't quit. Because if they do, all their friends will be making more money.
OK, but such a question carries economic implications like inflation. I know the research of which you speak, but I think it's flawed as it doesn't include an economic control such as 'the average wage in both cases remains at $30k, so you and your contemporaries all enjoy a high degree of financial security'.
This explains in part why people can't quit. Because if they do, all their friends will be making more money.