One way to fund a public good is to charge for admission. But, we argued in class that this doesn't necessarily lead to efficiency. One problem is that the price that is needed to fund the good might be higher than the willingness to pay of some uses. Excluding those users is inefficient for a good without congestion. Furthermore, if some people aren't willing to pay the entrance fee and are excluded, then the efficient quantitycontingent on the users who would access itwould be different. This represents another aspect of potential inefficiency