Good point, Gerry. Kawasaki pulled out after Danny got killed racing down there a few years ago. It was starting to get out of hand and that was the breaking point. People who've raced down there all have stories about close encounters with locals who make the course more "interesting" or with law enforcement and banditos everywhere.
Then there was he monetary issue: to keep rider safety as high as possiblt, top teams elisted helicoptors and other high-tech devices to keep tabs on riders and course conditions. It started to be a case of "who wants to write the biggest check" to win down there. Too bad, really. Everybody who's ever raced down there has balls the size of watermelons, the density of which are overshadowed only by iron ore.