Why is it that I can never run fast enough in my dreams?

Last night I had a dream that I was leaving a supermarket, one of those huge ones like Cosco. It was on the side of a hill in an urban area. As I walked out, I saw a suspicious person, and someone who I instinctively knew appeared out of nowhere and greeted me. I knew that I was dreaming, so I told her to help me run (since I can't run well in my dreams.) The suspicious person turned into this guy from my math class, and he was stoned out of his mind and vulgar, as per usual. The three of us got into a car, and it suddenly got dark out. I fell asleep, and I woke up hearing "Mama Will Provide" from Once on This Island on the car radio. I was in the car with the guitarist from my band, and these two other people who said they were her parents. It was so bizarre.