It wasn't inexplicable, it was a tradition going back to the first Capcom Cup.
Capcom had offices in San Mateo, CA, in where Combofiend worked as SF4 community manager in 2012. The Cali SF scene was very strong, had 2 majors (Norcal and SoCal regionals) and it made sense for the era to have the finals there. Now Covid killed the west coast Majors, and Capcom didn't offer to help with rekindling it.
I was at the first qualified CC, 2014, at the Warfield in San Francisco. A small theater and the atmosphere was electric, to see players like Daigo, Momochi, Xian, and PR Rog so close and personal. The crowd was amazing, full to the brim, with no lack of attendance or interest. Ono took the stage after grand finals to make his trademark announcement speech. A whole crowd photo was taken and we did a shoryuken. It was peak community. We even had a performance by the Mega's, and DJ iPad (A_Rival).
Now that Capcom has yanked CC away to Japan, yes, the attendance is strong. But keep in mind, they claimed "20,000 visitors" when in reality, that sumo arena only has 11k seats. It's a marketing trick because they meant 20k across all ~3 days of the event, not seated at once. Their quest for growth makes perfect sense from a business point of view, but the community still doesn't really benefit from it - case in point, they made the CC stream a PPV now. They tried to make it $40, bundled with SFL, but the community called them out on that and they backtracked. After 15 years of being free, quite inexplicably.