Earnings don't have to be paid in cash; payment in kind is also fine.
One month's worth of rice would be equal to my 3 hours' labor, and the
right to have a date with a pretty girl would make me work for 5 hours.
Money is a very good device in making the trades smooth, but may not be a
good one in making our life happy. Payment in kind can also increase
production and employment. To increase income is not only a solution to
better life, but to satisfy our everyday life is also important.