@jerrynord There are two reasons to wear a mask -
First, as you may have heard, anyone, whether symptomatic or not, can have this virus and spread it through droplets from their nose and mouth to others. Not just through coughing or sneezing, which really spray it to to wider area, but simply by exhaling as well. Wearing the mask as recommended protects others.
Second, when it comes to getting infected, the total amount of virus exposure and where it lands on you are both factors. The corona viruses are known to be able to attach to mucus membranes and the lungs. It is possible to get a virus through your eyes however, they are a much smaller target than the entire respiratory system, and a significant number of droplets would have to get right into your eyes to infect you, so less risk of infection there. I suppose if someone sneezed right into your face there would be heightened risk of transmission through the eyes.
So the key reason behind personal protection (the mask) plus increased social distancing, cleaning frequently touched surfaces, rigorous hand washing, and keeping hands off the face is to limit the amount of the virus that gets into the body and thereby reduce the likelihood of infection.
As a side note, the reason there is such a furor about the lack of adequate personal protective equipment (PPE) for health care providers and other front line personnel is that the TOTAL VIRAL LOAD they face day after day is what is causing so many to become so ill. That is why it is so important to also protect workers like those in the grocery store by keeping a safe distance - to minimize their risk. And why it is important to insist that medical workers be protected with proper attire.
Sue