The government recommends that people in high risk groups get flu shots yearly. They don't suggest everyone get them for mostly economic reasons. To their list I would add all residents of Hawaii because of the huge numbers of visitors from all over. People who should strongly consider getting vaccinated include all health care workers and anyone who cannot afford an unexpected illness. This would include the self-employed, critical employees and most serious athletes.

The flu can be a serious threat to older individuals, those with heart or lung problems and anyone with cancer or an impaired immune system. If you have contact with any such person you should get a flu shot to protect them from getting the flu from you . You should also encourage them to be vaccinated. Each year the flu causes tens of thousands of deaths in the U.S. alone.

This cost+risk/benefit ratio greatly favors widespread immunization. The flu shot is not 100% protection but if you get it you are less likely to get sick with the flu. If you do get it anyhow your illness will be shorter and milder because you had the vaccination.