There are many examples in which something free, useful, or both, causes frustration to people who are supposed to benefit from it. Aid to underdeveloped regions cause frustration. New government information websites in China, with their horrible UI and zero usability, cause frustration.
Hidden costs can be hard to see with foresight. And they often cannot be valued in dollars. UI issues mean that people spend more time scratching their heads, and less time for productive work. Social, political and economic problems with developmental aids are well documented. When the user/receiver perceives high hidden costs, frustration is felt.
Frustration is a subjective feeling. Its honest expression in a social setting helps the community sort things out. Gatekeeping feelings, therefore, is often counterproductive.
