The "independent" licensees are often subject to the policies and dictates of a district office who control the "independent" licensee's participation in various mileage promotions and rate settings. I have found that despite the best of intentions, sometimes the "independent" licensees are not fully informed of the district policies which makes it even more difficult should a renter encounter a problem (obviously they only "see" the local licensee, not the district office which actually sets their policies, etc.. Also, the "independent" licensees in some instances are "scared to death" of losing their franchise for violation of certain of Budget's rules and regulations, which certainly sets a certain tone as to their conduct...
I guessed the independent licensees in and around the same airport are probably owned under the same umbrella. They typically allow one-ways within their network, but often deny rentals from or especially to corporate stores.