Prior to going to college, I vaguely remember going a couple of times to get one at the doctor. Once I started college, I've been getting one on my own regularly every year. At college, we had free flu shots every year around November, I think, at various locations around the university, including my dorm. I'd always get one the day they came to my dorm. Now that I work, we get free shots every year on Safety Day, which is usually in October.
Nurses come to our office every year and give it for free.
We can get flu shots for free at the hospital where I work. In fact, sometimes a nurse comes around with a cart and gives you the shot right at your workplace. If the nurse comes up, I get one. If not, then I don't. Honestly, I can't tell any difference between the years I take a flu shot and the years I don't.