Part of the rationale for using Winthrop is to be able to put on a spectacle, and they've done it better than anyone else. The USDGC put prestige into an event, at a time when tournaments were all about the same -- and Worlds, just more of the same (more rounds, more days).
There'll be a large gallery following the event. They've sold out of $200 tickets and $50 tickets, and the remaining 1-day tickets are $20. Nowhere else are large crowds of people paying real money to watch disc golfers in person.
Yeah, it's not the greatest property for disc golf, and some of their experiments have flopped. But I'm willing to cut them some slack, for what they've accomplished. And people still seem to care more about this event, than any other except (perhaps) Worlds.