But the harm may go deeper than a mistaken view of human psychology. According to Graeber, once one assigns specific values to objects, as one does in a money-based economy, it becomes all too easy to assign value to people, perhaps not creating but at least enabling institutions such as slavery (in which people can be bought) and imperialism (which is made possible by a system that can feed and pay soldiers fighting far from their homes).
Trade did occur in non-monetary societies, but not among fellow villagers. Instead, it was used almost exclusively with strangers, or even enemies, where it was often accompanied by complex rituals involving trade, dance, feasting, mock fighting, or sex—and sometimes all of them intertwined. Take the indigenous Gunwinggu people of Australia, as observed by the anthropologist Ronald Berndt in the 1940s:
It helped that she had something other people wanted. “If I had gone in and offered to bake a pie for a free night at their hotel,’ they’d probably have said ‘no.’ ” One Barter Babe, Carly Boyce, knitted Simmons an exact replica of a favourite hat Simmons had lost but luckily had a picture of herself wearing. When it came time for the trade, Boyce remembers feeling guilty because the hat was so easy for her to make, and she told Simmons so. Simmons laughed: it was incredibly easy, she told Boyce, for her to give financial advice. It was a funny conversation, Boyce says, but also one that gets at the essence of bartering: when money is taken out of the equation, value is a moving, customizable concept—and that’s just the way most barterers like it.

It is estimated that over 450,000 businesses in the United States were involved in barter exchange activities in 2010. There are approximately 400 commercial and corporate barter companies serving all parts of the world. There are many opportunities for entrepreneurs to start a barter exchange. Several major cities in the U.S. and Canada do not currently have a local barter exchange. There are two industry groups in the United States, the National Association of Trade Exchanges (NATE) and the International Reciprocal Trade Association (IRTA). Both offer training and promote high ethical standards among their members. Moreover, each has created its own currency through which its member barter companies can trade. NATE's currency is the known as the BANC and IRTA's currency is called Universal Currency (UC).[28]