Fast Food Customers WTF?!

I work at Arby's. It's a great job for a sixteen-year-old like me in that it's easy and nearby. We have a little-known sandwich called the Super Roast Beef. I've seen it ordered maybe five times in the three weeks I've worked there. I had one ordered today. For some reason, I find that name to be quite comical. I mean, what could possible be so "super" about a sandwich. I didn't know what was on it; I don't make the food. So I went into the back and asked my manager who was making the food, "What makes a Super so super?" At that point I noticed on the big board of how all the sandwiches are made that a Super is simply a Regular roast beef sandwich with lettuce, tomato, and red ranch sauce. Knowing that the Super costs a dollar more than the Regular, my manager responded, "It's a super sandwich because it's amazing that people are willing to pay that much for lettuce, tomato, and red ranch sauce." It brings up a great point. Why are we paying so much for fast food when we could simply walk into a local grocery store and buy some meat, cheese, and bread and make a comparable sandwich? I often have people drive up to the drive-thru and order a single Regular, which costs $3. Is that really worth it? $3 for 3 oz. of roast beef and a bun? Maybe people are just stupid, but I could get so much more food for three bucks. It's just ridiculous how much people will spend on fast food.