You shouldn't be. It is protective measures. It is done under assumptions that anything has potential to be source of infection. This is only way to protect the ramp workers. Remember a report about Heathrow baggage handler being infected not long ago?

In China you have to wear a face mask to take public transportation or even go to shopping malls. Europeans and Americans may find it intrusive. But as an individual, I feel much safer to have a mask and see other people wearing a mask too. It is a personal choice. Unfortunately for those cargo loaders, the protection wear is their only choice at this moment.