The more I try to comprehend the whole notion of the book, the more it answers my curiosity about "Why were they not running?". It's about human nature, we don't deviate from the expected, and these kids have been raised their ENTIRE lives to think it's their fate, their duty even, to donate their organs. They do what's expected of them and what they've been raised to do. Few humans would act differently or contemplate another path with such a limited experience as these characters have had- there are those one off individuals who would rebel but this book isn't about them. That's what makes it so tragic, all along these characters have been seeking an escape within the confines of those who created them; deferrals, the gallery etc- they didn't have the perspective to look beyond these boundaries, nor did they see them as boundaries.The final line of the book sums this up 'I drive where I'm supposed to be.'