You should use your words in a better way if you'd like to convey why these companies should have to "buy" "employees" who were educated by the state. You should also explain how these companies are more special than others and why they in particular need to pay. You should also explain how they should pay in some way meaningfully different from the taxes we already pay.

But mostly, I am curious about what you actually mean about buying students. I'm not being obtuse, I don't understand what you meant because I'm sure you're not really advocating what it sounds like.