The players choose their own shoes. They know the dangers of wearing the lighter weight, less supportive shoes. As for the turf, the Saints and all of the others teams using these surfaces made the decision to use these surfaces.

Another reason being raised for the high number of foot and ankle injuries throughout the league in recent years is the athletes themselves. They are faster, bigger, and stronger than ever before and those feet and ankles simply are not genetically designed to withstand that pressure.

Here's an article stating the same I just found.

How foot and ankle injury trends reflect today’s NFL

As with most sports, the NFL players themselves have gotten bigger, stronger, and faster, in combination rather than isolation. A bigger man running faster has greater forces that he must dissipate. Even as the muscles higher up the kinetic chain are getting bigger, feet and ankles are essentially left with the anatomic gifts of a player’s genetics. And, while advances in the design of shoes and cleats have led to exponentially better performance, it’s clear that one thing the expensive shoes aren’t doing is reducing foot and ankle injury rates.