One-way Mars mission?

One of the biggest hurdles to a Mars mission is the sheer cost and complexity of getting the astronauts back home. So, why not just leave their asses there?:

We might want to restrict the voyage to older astronauts, whose longevity is limited in any case. Here again, I have found a significant fraction of scientists older than 65 who would be willing to live out their remaining years on the red planet or elsewhere. With older scientists, there would be additional health complications, to be sure, but the necessary medical personnel and equipment would still probably be cheaper than designing a return mission.

This guy does have a point. Wouldn't someone like Richard Branson totally be up for this? I still think, though, that the prospect of developing technologies to extend our resources here on Earth heavily outweighs the potential of colonizing a planet that is 36 million miles away.