I think it also depends on where you live. There isn't much access where I live. There is one free clinic here in town that operates at night one day a week. Thing is, you have to make an appointment, and they only see 18 patients a night. The way they do things is really unfair. You have to call during that day for the appointment. And if they fill up their appointments that day, will they start booking for the next week? Nope. You have to wait until the next day and try your luck again. My boyfriend tried to get in, but after the third week he gave up.
There is another one about 25 mi away that doesn't require an appointment. However, you have to pay $75 at the time of the visit. If you don't have $75 that can be a problem, and that doesn't include medication. Hell, that's about what my family doctor charges for an appointment, so how does that help anyone? In this area, if you don't have insurance, preventive care isn't really an option. It's either get up at the crack of dawn and try your luck at the clinic, or wait until you have a real problem and go to the ER.