Of course, they won't actually get health insurance for it, which will cost a family ~$20,000/year. That's about 6-13% of your paycheck that could have been going into your wallet.
Also, don't forget your state income taxes, which will scrape another 0-7-12%.
All-in-all, Americans pay ~26% of their GDP in taxes. People in the UK pay... ~27% (Edit - it's actually closer to 33%) of their GDP in taxes. [2] 'Americans pay less taxes' is largely a meme with no basis in reality.
[1] Just because that gets subtracted from a different line item on your W-2 doesn't mean that you shouldn't count it.
[2] This is the only meaningful apples to apples comparison of overall tax burdens. And it makes the US look really bad, because that 26% won't even get you healthcare. Or cheap university tuition. It does get you 11 carrier fleet strike groups, and 5,500 nuclear weapons, though.