One of the FEW things I actually agree with Musk on is for the human race to survive we HAVE to move beyond Earth. Even if WE don't make it uninhabitable, we're only one cosmic incident away from extinction. True currently, we don't have the tech to have permanent settlements on Mars etc. but that could change. Problem is Musk wants to be the one who does it and he will cut any corners necessary to ensure he gets there first in order to claim the glory.
As far as no positive benefit from private space travel, I'm not convinced. While I would prefer publicly funded space exploration, I do believe there is room for private exploration as well, but it HAS to be regulated in a sane manner.