I eat fast food alone quite often. When you are hungry, you are hungry. People will just assume I'm grabbing a bite on my way to work or some other important place. Have never felt the urge to have a fancy dinner by myself. I only do those with the girlfriend and good friends.
Similarly, I watch a lot of movies alone. But that's because most of my trips to the multiplex are last-minute nick-of-time type affairs. I will be home at 10PM, feel like watching a movie that starts at 10:30 - which gives me 30 mins to get dressed, start my bike and race like a mad man. Most of my friends need at least an hour just to get dressed, shave and gel their hair.