i see it as a way your not inclined to touch your face when your wearing one, yes it does nothing but it's better than wearing a water bottle on your head
By itself, the mask won't do much of anything because the virus can still be on your clothes or get in through your eyes. Medical workers or lab workers can make use of them because of the other equipment like suits and goggles, as well as the removal procedures involved.
It can still help somewhat for regular people if they're infected as you can't easily spread it around from random coughing as well as keep you from touching certain parts of your face. But if you don't need the masks, don't buy them. There's a bad shortage going around in hospitals all around the world. And since the removal procedures involve immediate disposal of a mask, I've heard cases of medical workers getting dehydrated because they're trying to conserve their stocks by not taking them off even for a drink.
