First, this is not like any other disease we've had to deal with in our lifetimes, as indicated by the worldwide quarantines. Shit, China doesn't give a shit about its citizens and has done far more strict quarantines. Second, the whole idea behind the masks is to mitigate the risk. You want moderately vulnerable 50-65 year olds out working, consuming, etc. to help the economy. If wearing a mask makes it safer for me to work (two days in the office/week), occasionally eat at a sidewalk cafe, and go to stores to buy booze. In other words, wearing a mask reduces the need for quarantine (or reduces the severity of it).