Perhaps but there will then come a time were we might have to leave this planet, and i for one hope we have some trained people to get us moving. As well as populations on the moon. 1 asteroid can ruin our whole day.
If you're seriously worried about an asteroid strike, maybe we should consider funding asteroid detection projects (currently underfunded) for 1/100th the cost of a manned mission. The cost of coming up with a way to deflect or destroy an incoming asteroid would still be a minuscule fraction of the cost of sending some clown to Mars, let alone actually putting a permanent population on the moon.