Some athletes earn millions per month - is this due to market inefficiency ?

I understand that Cristiano Ronaldo and Neymar have unique skills

But millions of people play soccer (basketball, tennis, etc.)

It's not possible that it's so difficult to find someone really good and sign a contract stipulating a maximum salary of $20,000 for the next 30 years.

I am inclined to believe that there is an inefficiency in the market.

Teams would be able to find very good people for less money