A lot lf Americans just don't think about it that way. There's a multitude of reasons based more on sentiment and group social pressure than the obvious math.
Many Americans have a great deal of personal optimism to the tune of "well I'm not sick right now". It's a gamble that everyone loses, but in the short term you keep more money. It speaks to the belief that personal heath is a moral virtue (or failing), therefore a moral person shouldn't have to pay for immoral people's "bad choices". And, if someone didn't save enough money to invest in their own health, that's also a moral failure.
There's also terror of appearing too feminine. Care, either receiving it, or giving it to others, is feminine coded for a lot of Americans. So, paying into (and participating in) a broad public healthcare system becomes a crisis of masculine self (and group) identity. sarcasm You wouldn't want people to think you're a sissy right? sarcasm
Er, sorry for the wall of text.
Tolerance is for anyone, not everyone. When someone's "opinion" is that innocent people should be deprived of life, freedom, and dignity, it stops being an opinion and becomes a violent threat.