Originally Posted by ModelPerfect

Naw, certainly not plot holes...just science holes of the non-black variety. ;)
1) Exactly. The energy expenditure required to reach our planet (using current known physics) would be far greater than that acquired by turning out entire planet into energy...so there's really no economic incentive.
2) True...the poor alien could have been conserving fuel and trying to process enough to make it home when the human cracked the hull...
3) According to Einstein, the universal speed limit is the speed of light...nothing can move faster that that, at least not anything with mass, so there's no traveling 5*c. Again, that's based on our current and incomplete understanding of physics.