Sorry, man, but I disagree on all those points. To sprint, you definitely don't need full track facilities, you just need a decently big patch of grass! ;) I do most of my running at a local park. The stamina and endurance you're talking about is built exactly BY doing sprints. What you're saying is like "I can't deadlift 300 pounds because it's too heavy, so instead, I'll continue deadlifting 50 pounds forever."