In addition to all the reasons others have mentioned, I've also read of multiple people who submitted all of the required paperwork and were denied multiple times, even though everything was appropriate. Of our group, every single couple had at least one denial, and had to resubmit, some while waiting at the airport to board their flight. Add to that, the problem of employers requiring quarantine after returning home, states imposing lockdown, and the uncertainty of airline schedules, I completely understand some people cancelling. We are here and are enjoying ourselves. I do feel safer here than I do at home, mostly because most everything is outdoors.