Inertia, probably. Any gradual change adds to the bloat; any radical change is rejected out of fear, or maybe ideological concerns.
Not picking a fight here, just curious: another person commented on my original post noting that when I said my first birth didn't cost us anything, that wasn't true - my wife's employer paid a fair amount for her insurance.
Are your taxes broken out in the UK? Do you know how much you pay a year for healthcare?
For my family it's about £2800, or $3900. My wife doesn't pay tax, but I earn in the top decile. Probably a little more due to spending on vat and other indirect taxes (petrol tax etc), call it $4200.
However my parents, gran, and my mother in law combined pay under $1000 a year between them.
On the other hand a premiership footballer pays about $250,000 a year for health. Plus their own private health care costs of whatever. That's the price they pay for living in our society though, a society where people aren't afraid to go to the doctors to check out that mole, or rush to give birth because they can't afford an extra day in hospital.
(Cost of bringing my children into the world was about £10 - the petrol, the parking, and I bought a chocolate bar and bottle of water at one point)
Why does America stand for it?