Luke didn't care about that at all.
As the owner of an alien planet who was still putting down roots on a lawless planet, Luke didn't have to care too much about the actions of the governments on Earth.
In any case, with CEO Jenny and the bigshot who sold everything working in tandem in the light and behind the scenes respectively, it wouldn't be hard to wrest superhumans from the governments.
It was absolutely impossible for these government bigwigs to be clean and honest; making them 'work for free' was easy as pie.
Money and credit points were meant to be spent, and Luke didn't lack either.
Using them to consolidate Earth's standing as a base for harvesting points and training talented individuals was the right choice.
In any case, as long as Luke did things for the good of Earthlings, the system would give him experience and credit points; it didn't matter if the criminals had superpowers or not.