I live in the Atlantic City area. Just looking in my Yellow Pages, I'm seeing all kinds of ads for the big rental car companies in South Jersey. I'll assume you're closer to Philadelphia, as that's where more of the population is.
I see
Avis in Cherry Hill, Deptford and Mt. Laurel.
I see
Budget in Blackwood, Burlington, Cherry Hill, Deptford and Palmyra.
I see
Enterprise in Cherry Hill, Mt. Laurel, Maple Shade, Cinnaminson, Somerdale, Pennsauken, Mt. Ephraim, Runnemede, and so on.
I think you get the idea. You're not limited to airport locations.
And as a native Northeast Philly boy, I'd only suggest going there if you're north of there or right across the river. Otherwise, you'll be unnecessarily going out of your way.
Happy Hunting!