Two things. First, If the difference was $500 on property $50 off property we would not be having this conversation. The difference for me is around $50-$100 per night thanks to being a TA. Second, flying out of Jacksonville sucks and can be costly. Flights from JAX to LAX typically start in the $400 range. To only other option is to drive 2-3 hours one way to Orlando and pay for long term parking. With a party of 4 that can save a decent bit but it is a major freaking hassle. I can drive up to 7 people to WDW for about $60 round trip
Like I have said until I am blue in the face, with my situation my money goes considerably farther at WDW than it does at DL.