I think because of our more and more fast-paced culture people have neither the time nor patience to cook. Working families settle for boxed or pre-packaged convenience items because they feel like they don't have time to make anything from scratch. The horrible thing is that those foods are often loaded with preservatives and all kinds of things that really aren't too good for you.
I feel like TV personalities like Rachael Ray are really starting to revitalize an interest in cooking, in America at least. I've yet to actually make a 30 minute meal that only took 30 minutes (I average about 45 minutes), but the fact that I can make something healthy from scratch even on a weeknight is great. I wish more people would realize that if you plan ahead and keep practicing, cooking really isn't that hard.
I learned to cook about four months into my first year of grad school. I was relying on a lot of boxed foods, and one night while I was eating some Hamburger Helper, I finally said "Cooking can't possibly be that hard" and asked my mom for some recipes. Now I love to cook. I try to make several extra meals on the weekends to portion out for the week, since I don't get home from work until 7:30 or 8 on three nights, but if I keep the right ingredients on hand and keep my fridge stocked with veggies, I can always eat well, no matter how busy I am. It's when I don't plan ahead that I end up eating junk.
Good, independently owned restaurants seem to be a dying breed. My parents like to go out for dinner on a Friday night, but a lot of times they end up settling for something that's really not all that good because there aren't any great restaurants in my hometown. I keep saying to myself that someday if I ever get tired of teaching, I'll open a restaurant that focuses on simple, healthy, cooked from scratch food. That's what people really want, and it seems to be getting harder and harder to find.