I see masks as having two distinct purposes : 1. To protect me and my family members when we need to enter a "hot" area such as a virus-denier-owned business or other place with large numbers of people and poor ventilation. We use best available N95 type masks (KN95 for example are widely available now) for this purpose. 2. as a signal I can read from other people as to whether or not they take virus spread mitigation measures seriously. So if I see someone not wearing a mask in a store, I can reasonably assume that person is more likely to transmit the virus. Not because the mask they're not wearing is not effective, but because the lack of mask tells me that they probably mix with other people, frequent places with large numbers of other people, are friends with people who don't take quarantine seriously, and so on. So even if masks had zero effectiveness for virus transmission, they're still very useful to me in identifying people and places to avoid.