But when a coworker has a cough or cold, they wear a mask all day. I'm sure it looks strange in an office setting, but it makes a difference in preventing the spread of germs.
My pet peeve is when truly sick people don't call in sick to work. They risk getting the whole office sick. So, if they are going to come to work, the least they can do is wear a mask so they don't get everyone else sick.