In 95 the FCC did an investigation into the PGA and found:
"One of the rules forbids golfers to play in a non-PGA event without the commissioner’s permission. The other gives similar veto power over appearances on televised golf programs. Together, the provisions enable the PGA to dominate the business side of professional golf, constraining the opportunities of rival promoters."
The PGA was able to convince the FCC those were critical to the PGA growth, which they shown was happening.
The environment today is quite different and I think Lawsuits will be flying, especially since the other tours are doing the same as the PGA.
It's all the dollars..