I would argue that for certain things like painkillers they can be essential for quality of life and ability to function, but not for something that is "life threatening".
I'm not sure under what circumstances you're seeing them prescribed as IIRC around my way they stopped prescribing a lot of lower end pain relief years ago, but my mum used to get paracetamol on prescription (along with IIRC 2 or 3 other different types of painkiller) as her condition required the mix and short of popping into the chemist every few days it was the only way to get enough, as it was we'd always pick more up if out because the GP prescribed them in boxes of 100 (so the combination of buying and prescription meant she didn't have to go shopping every few days specifically for them and the gp was only doing one prescription for them a month).
I would also suspect that if you started charging for meds that were prescription but not for "life threatening" conditions you're going to add a whole new layer of complexity and cost to the prescription system, adding more work for pharmacists and slowing things down at a time when most of the pharmacists I've seen are already struggling to manage with the workloads, and as a bonus going to end up with people not getting medication that is for "non life threatening" conditions and those conditions turning into "life threatening" ones.
For example IIRC Omeprazole is required if you're on high doses of ibuprofen to help prevent stomach ulcers/damage to the lining, but as until you've got that stomach ulcer/damage it's not a "major" issue (and once you've got the damage it's hrder to deal with).