Because it's a lot easier for the Vegas mob to get to a team of officials rather than random selections. Goodell is actually an FBI plant and is working in concert with Congress to take them down once and for all. This is the latest ploy to make them desperate and expose themselves. The replacement refs were also FBI plants waiting for the take. It should have been obvious by the way they called games. In another year or two they'll start making arrests and all hell will break loose. Other sports will follow.