It enables patient autonomy. People increasingly make choices about whom to see and where to go for health care. Cost matters to patients. It answers questions about why health care is so expensive. Anyone with a smidgen of interest in accounting would want to know why things cost as much as they do.
People deserve an explanation, and once they see the numbers, they'll want one.
Educational level, savings patterns, family priorities, and other nonmedical factors are not aspects of patient care that physicians have been trained to ask about. Economically disadvantaged patients will be frightened off by the numbers. They can only be disadvantaged further by hearing prices they cannot afford. Health care should not be decided by cost, but need. The cost of a baby's vaccines cannot be compared to the cost of a lawn mower.