I agree with you… but I don’t see it as a rhetorical question at all. The greedy folks who crave more riches, more things, more power, more more more, have successfully bamboozled most people into thinking our current system is natural, “just the way the world works,” that there are no realistic alternatives. That was drilled into our heads over and over since we were kids (I know I heard it a lot.)
But it isn’t true. And that’s the point. Once you realize the why we don’t is due to greed, due to choice, we can realize it doesn’t have to be that way-- we could choose another path. That’s how the question can radicalize folks… hopefully. 
Via @mindysan33 here
(I only wish I knew how to get us there.)