Why are well-paid workers given health insurance and poorly-paid workers left to fend for themselves?

wouldn't it make more sense to give low-wage people affordable health insurance and make well-paid people pay just a little more for their own premiums? Maybe I don't understand it very well. Can somebody explain it to me? I really want to know.
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It's because of bad government policy. The government in our country won't include social factors into the free market economic system. In Europe and Japan, they have established a national health care program.It's subject to all, rich and poor. The rich can pay more premium for their comfort anyway.
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