Arguments for: They are paid more based on services rendered than on current or future contributions. Since when is this how things have been done? Besides, how much money does Kobe Bryant need, for example? To date, it is already do over $303 million over the course of his career, which, by the way, has basically ended since 2013. And he only has $25 million more left!
Arguments against: They are paid according to the value that the market has determined. Ideally, a professional athlete’s career ends at age 40 – even 35 is generous. So the few who make it this far and win championships along the way have earned the right to be overpaid for a few seasons and don’t care about public perception.