The protection provided by the vaccines against COVID is not infection per se. It's protection from disease serious enough to need hospitalization, ICU care or death. Some people can't get the vaccine because of medical problems (many of those medical problem leave those people at risk for serious disease). Some vaccinated people the protection will only partially take or will not not really take at all. In unvaccinated populations (the bad old days of 2020) about 15% of infected people will get severe symptoms requiring hospitalization, 5% of infections will require intensive care, 1% will die despite all care. The problem with COVID is that it is very contagious, more contagious than influenza (with pandemic measure the last flu season basically didn't happen despite COVID still spreading readily). So, since spreads rapidly then a very large number of people can become infected, in a chain reaction, at essentially the same time. A small percentage of a very, very large number is a large number. So, in a large metro area (~1 million people), if 5% of the population caught COVID in the space of a week or 2, that's 50,000 infections. 15% of 50,000 is 7,500 needing hospitalization. The OSU Med Center has around 1,300 total beds, Riverside has ~725, Mt Carmel East ~575, Mt Carmel Grove City ~210. That's a little over 2,700 beds. Of the the 7,500 needing hospitalization (average length of stay 6 days) ~2,500 would need ICU care (average length of stay 15 days), 500 will die. If beds are outstripped even more will die because the people who only need supplemental oxygen and monitoring won't even get that. That's what happened in India recently - hospitals running out of oxygen, people dying in tents outside of hospitals and in cars in traffic jams to hospitals. It looks like some vaccinated people can catch the virus, the vast majority asymptomatic. The worry is that every time there is an infection (symptomatic or asymptomatic ) there is massive viral replication with a small percentage of RNA replication errors, many will result in no meaningful change in virus behavior, some errors will be make the virus less virulent or even be fatal to the virus progeny of that strain, some will result in increased virus virulence (more contagious and/or producing worse disease). So, the concern is really for others, the healthcare system & society. It's actually not fear of personal harm. So, don't be angry. Check yourself in situations where you do not understand what people say or do. Be humble and curious instead, because you may have incomplete or incorrect knowledge.