It is not a waste of resources. The car was built, it was used for its purpose. Now it is being sent out of the planet so you could argue that the overall amount of trash was reduced.

Also "Space is big. Really big. You just won't believe how vastly, hugely, mind-bogglingly big it is. I mean, you may think it's a long way down the road to the chemist, but that's just peanuts to space"