Indeed! We do need to consider bang for the buck, and we need to consider it not just in the context of "What cool stuff can we do that involves hurtling some mass to escape velocity?". That's cool fun stuff and I grew up on a steady diet of wonder at what NASA accomplished. Sending a man to the moon to whack a golf ball was really cool, even if it was mostly pointless, and we did it at a time when we could better afford it. Today, we have to make wiser choices because our collective resource pool is greatly overextended. We're risking that one day our grandchildren are going to look back and wonder why we sent toy cars to Mars when we could have been addressing the huge problems that we're leaving to become their daily misery.
NASA can do many great things that would be to our collective benefit, from deploying technology into orbit to feed us more and better data about our warming planet, to figuring out how to adjust the trajectories of asteroids, meteors, and comets that could do us serious harm. Those things I can get behind. Diverting our best minds and limited resources to perpetuating the fantasy that after we've made Earth uninhabitable we can just escape to some other planet is just plain irresponsible foolishness, so we don't have to send people (or toys) to Mars unless/until we've solved some more pressing problems and can more readily afford to indulge that foolishness -- if ever we can afford to indulge it.
Thanks for a fun conversation!