Long ago, it was barter system. People used to trade the goods among themselves. They used to offer the goods that are in myriad, in exchange to the goods that are in dearth for them. It was, in this way, trade was evolved. Later, it was with bronze and other metal coins used for trade and called it as selling and purchasing. And now it's money that is being used for transactions.
Along with this, the interests of people also evolved and varied from one-another. Basic necessities are not the only ones that people are buying now. Market too has evolved. Manufactures and business men made things that enticed people to buy the things that are creative and good looking. So, in this process of creating new things and buying, market's revenue has been multiplied.