I don't see this as a form of socialism, but more like recruiting incentives, which are relatively cheap for the government.

If the value of a life is aprox. 10 million USD, and they had to pay the family of every dead or disabled soldier that amount, it would cost significantly more, no?

Or: if you take the number of dollars it would require to get the sons of Kennedys or Trumps to join the army (and risk their lives in combat), and gave THAT amount to every soldier, that would be socialism.