Someone posted something in here a few days ago that I can't find right now, but apparently this was a huge thing in Australia at least. I believe the report said that like every Chinese company suddenly made it their top priority to raid the country for medical supplies and ship them back home. It sounded insane, but I'm seeing a lot of corroborating evidence from other parts of the world.
To me it's not surprising. It's pretty much only people that have grown up in the West that look to abstract principles to explain human behavior and view everyone as an atomized individual as if you came out of nowhere and have no past/history that's important or identity. A large portion of people in the US from other countries/cultures, even if they have issues with those countries/cultures and don't want to return to them, they see themselves as part of that country/culture first. They are Chinese first, Mexican first, Filipino first, really there are people like that from pretty much everywhere except Europe.
Besides that, it was probably a moneymaking opportunity either for the individuals or the company. We'll probably see lots of non-Chinese doing this the next time it comes up. Plenty of people hoarded supplies as soon as they knew there was a shortage and tried to sell it on Amazon/Ebay or even on the side of the road, and the companies and or law enforcement had to put a stop to it. Well if people find out there are foreign buyers you'll have plenty of those people doing this next time to make a profit.
If you want to be protected in a time like this from bad behavior, you need a country of nationalists. If you don't love America more than you love other countries, which a lot of liberals don't, then there is no reason to sacrifice for it. If you want to have a country, you cannot have one political party that disparages it or teaches others that it's bad.