To be clear, it isn't free healthcare. In Canada we pay our taxes and the government administers the health insurance system. In Ontario where I live it's the Ontario Health Insurance Plan. It covers most doctors visits and most treatments. I have Hodgins Lymphoma and am nearing the end of my treatment. Dozens of doctors visits, CT scans, x-rays, an echo cardiogram, a respiratory study, two PET scans, and all the drugs and the only thing I've paid for out of pocket is parking, and the hospital where I'm being treated just put in free parking for cancer patients and gave me a parking pass. Our government negotiates the price of drugs at the national level and regulates drug prices. Companies aren't allowed to raise the price of a drug that is on the market unless there is a corresponding improvement in benefit to the patient. They can't add a coloured band to a capsule, rename the drug (Losec to Prilosec, for example) and double or triple the price. Generic drugs are the same. That's why epipens are $100 here and not $600 like in the US. There has been no substantion improvement in their benefit to patients so the price can't go up.
Universal healthcare isn't perfect but 22 of 23 highly developed countries in the world have it and the US profits before people system is grotesque.