Instead of waiting for someone with the flu to develop pneumonia and go to the ER because he can't breath, it'd be much cheaper to subsidize his visit to a primary care physician that he can go to before he needs a hospital.
To relate a personal experience, I have a relative that's had drug addiction problems all her life -- a few years back she had a cold or flu, couldn't afford to see a doctor so tried to ride it out at home, fortunately, she called her mom and told her how sick she was. When she didn't respond to the phone the next day, her parents drove across the state to check on her, found her near comatose and called 911. She had some bacterial pneumonia and almost died, she spent 10 days in the hospital, 5 of those days were in the ICU, intubated and in an induced coma. Because she was working and had some moderate income, she had lost her eligibility for state subsidized medical insurance. After taking 6 weeks off work to recover, she of course, lost her job, then she qualified for health care coverage and state disability payments.
The total hospital bill was over $300,000. Since she had no income or assets, the hospital wrote off the entire bill and absorbed the charges.
All of this because the public didn't want to pay $100 for her to see a doctor and get some antibiotics.