We eat out most nights. I work from home, my DH dosen't work and our one child who is old enough to go to school is homeschooled (through a public school program). We are home together all day, everyday so getting out of the house to sit down and enjoy a nice meal is a sanity saver. Plus, between work and schooling my daughter, I don't have time to cook and clean up after dinner everynight.
For us, we don't go to Disney to eat, but we did QS last time (except one meal at Tutto) and I didn't like it. Plus, we have a lot of small kids, so it is nice to sit down and be served in the middle of a hot day. At the same time, I don't want to spend $150 per meal like we did at Tutto, plus $50 on a QS meal and $15 on snacks per day if I don't have to. For us FD is the cheapest way to go to Disney with a room, tix and food that I'm willing to eat.