I am not certain if the law has changed but I own a small plane and ran a small private public use airport in Connecticut from 1991 through the early 2000's. There was a State Statute that prohibited non State owned airports from receiving Federal funds in theory to allow the State to receive more (Windor Locks, Hartford, New Haven, Willimantic, Oxford, Danbury, Bridgeport, Danielson and New London). Other states do not have this regulation and that may account for some of the disparity. That law may have been changed or may be under review as I am aware of a program that provides Federal funds for municipalities to purchase small airports and there are some applications in the works.