As a concept, cheating itself is based on certain mechanisms in the economics realm. Economics postulates that in his or her pursuits, a rational person will always seek to maximize utility, or get the most possible gain from a certain course of action. By cheating, a person may be able to gain more while putting in less work, thereby maximizing the marginal utility (the effort put in subtracted from the reward gained). Thus, even rational people are incentivized to cheat, just like these schoolteachers and sumo wrestlers.
If the economy were allowed to work untouched, then it is likely that rational consumers and competitors would continue to cheat unchecked, since there is incentive to do so. However, this is where centralized agencies like governmental organizations come in. They seek to moderate the playing field and provide economic and social incentives not to cheat, as was the case with the board of Chicago Public Schools and the cheating teachers. This type of regulation works in small-scale situations like this, but it is also is at play in the larger economic world of firms, corporations, and businesses. Governmental regulation exists to make sure cheating remains at a minimum.