This is true but you have to look at the whole picture. It only costs $5 per day to park at the AC airport. And even though it's 25 minutes farther to drive than Philly, it's an easy on/off, no horrendous security lines, convenient parking, the plane never has to wait for a gate, assigned seats, etc, etc.
Plus I end up spending money during the inevitable wait time in Philly. I think our overall *transit* time is much less even though the AC airport is farther away.
Either way, don't book your flights yet. Start looking over the summer.
Jenny