Most of the wealthy NFL owners don't like being embarrassed by being called out for not having adequate facilities.
The New England Patriots and Kansas City Chiefs are known as good, winning franchises but they got some bad grades in last year's NFLPA poll. Chiefs owner Clark Hunt got an F- grade, despite his team winning three of the past four Super Bowls.
The point of the NFLPA poll, theoretically, is to shine a positive light on the model franchises and be a wake-up call to teams lagging behind. In the case of the Chiefs and Patriots, it seems like it worked.