"Aussie MMA Coach’s Trip to America Goes Horribly Wrong as He Ends Up in Jail & Deported After Arriving in U.S." - https://www.essentiallysports.com/ufc-mma-news-aussie-mma-co...
https://www.sportskeeda.com/mma/news-update-u-s-federal-pris...
"UPDATE: I just spoke with coach Renato Subotic for a few minutes. He says he was detained at FDC Honolulu, which is a federal prison facility. He says he has no criminal record and it was a simple visa application issue. Interview later this week."
No one wants to be detained.
People who are spending thousands and tens of thousands of dollars to travel are fine if they need to spend a few hundreds additional ro fly back and cancel their vacation. Or sucks but it’s in the realm of the risks you take with international travel.
However, being detained, even for 1 day, and treated like a criminal is something none of these folks want.