Because the Collective Bargaining Agreement permits owners to underpay the vast majority of players, teams can be reasonably expected to overpay for the rare player reaches six years of MLB service. That's the price the owners pay for suppressing the salaries of most players.
Why not do away with the draft and make each player a free agent regardless of years of service? Let the market determine how much each player is worth. That's the way employment works in many industries.
The excess money that now goes to the rare player who reaches free agency could be redistributed among the less experienced players who are currently underpaid. At the same time, without a minimum salary, owners could fill out their rosters with players who are willing to fulfill childhood dreams for, say, $100,000 or less annually.
Just a thought.