If you can afford it (or your employer pays for it), you get to use whatever. It helps cut some queue times, and gives you more choice and convenience.

Doesn't mean the free one can't still be "extremely good". I might pay for IntelliJ, even though a free IDE or even editor like Emacs is still extremely good.

And 40% of the population is still a huge number of people, who would otherwise had trouble affording private health care or get the shitty low tier and/or hella expensive private care afforded by the poorer in the US.

It's also not exactly like "50% of the population use private health care". It's more like "50% of the population ALSO use private health care", in addition to the provided free health care.