I am a pretty good cook and live with someone else who is a pretty good cook, so we do tend to cook at home far more often than we go out. It's much cheaper, we know what is going into the food, and to some extent where it came from (love the farmers markets in my area that have everything!). I also have IBS, and am lactose intolerant. It's amazing how many things have some sort of dairy in them. So, because of my stomach issues I tend to prefer to eat at home. However, there are a couple of chains I will go to for a quick lunch on the go (never fast food though) that do have healthier options. I also have a ton of really good independent restaurants in my area that I may go to once a month or so.
I think if I didn't have to deal with the dishes that cooking at home makes, I would make 3 meals a day at home. I HATE dishes.