I guess i can say some people go further than others but im not in favor of wasting time and will be flying out of JFK at 6:30 am.
I used to do the exact same thing when I lived 15 minutes from LGA and didn't yet own DVC. This was also back in the day when you could get to the airport 30 minutes before your flight--there was no security line to go through. We'd land before 10am, get the rental car, and maybe just lucked out, but whichever resort we were staying in always had a room ready for us to check in to. We'd unpack, and be in a park by lunchtime!!
Upon joining DVC, we discovered that when they say 4pm checkin time, they mean 4pm. And on our first DVC trip, we discovered that without that short "decompression time" in the room before heading to the parks, we be very cranky--and cranky people do not have much fun at WDW. :ROFLOL:
Now we take the 11am flight, get the rental car, stop at the supermarket for provisions, check in, unpack, and get to the park in time for dinner. :shrug: And since we now live 45 minutes from the airport, we still have to get up pretty early!!