Libertarian law professor Richard Epstein, writing in the Spring issue of National Affairs:
people concerned for their freedom and rights are always most alert to threats that arise when governments (or other powerful institutions) force us to do what we don't want to do. The power of coercion is more easy to define, to identify, and to resist. But we are not sufficiently alert to the flip side of this problem: the risks that come with the power to create exceptions and to grant dispensations. Indeed, this is a much more subtle, insidious assault by government: Rather than setting the state and the private sector against each other in a healthy tension, it fuses them, making the private sphere dependent on the government's benevolence. And when currying the favor of capricious government officials is required for a person's well-being or a firm's very existence, government abuse becomes nearly impossible to oppose.
"Government by waiver" is thus among the most serious challenges to the rule of law in our time.