I believe they postponed Expo West due to pressure being put on them from exhibitors and large suppliers (e.g. Well Well). There are certainly concerns, but perception and pandemonium rule. There's a lot of food and beverage handling and tasting at that show, so that may well be the worry. My missus was there but came back the moment it was called off, more out of fear of not being able to get a seat home than the virus.
Agree that the Disneyland situation is odd. Perhaps at Disney the greenback rules over everything else.