What athletes have in common with actors

In a books column on the sports business in the May 16, 2016, New Yorker, Louis Menand mentioned this:

The entire industry rests on the labor of athletes. The number of athletes is actually quite small, but, as a class, they are not getting that much of the money. According to the Bureau of Labor Statistics, only 13,700 people make their living playing spectator sports in the United States (compared with, for example, sixty-nine thousand people who are actors). The median annual wage for athl...