Some Americans don't even count the FICA taxes (social security/medicare contributions) as taxes. That way they can claim that the poor don't pay any taxes.

They're fundamentally different, one is a progressive tax designed to support a civil society (income tax) and the other is a regressive usage-based tax designed to dis-incentivize behavior such as smoking, drinking and using gas/private automobiles. One's a benefit driver, the other is designed a penalty or market force.

Ok, but they are both taxes, yes? And they both diminish your effective income. So, when calculating the relative tax burden between countries, they both count.

They do both diminish your income, but only if you insist on doing things society doesn't want you to do. Driving is optional, smoking is optional, drinking is optional. You can opt out by changing your lifestyle to be healthier and more sustainable -- in which case you'd not pay that tax in either country. Income tax isn't optional.

Sure, but you either are or are not willing to make those changes, and you presumably already have made them to the extent that you're willing. Whatever burden ends up being imposed based on your consumption habits simply is what it is.

True of course, but hard to factor in. If you move from rural America where a car is required the gas tax burden is going to drop substantially if you move to Amsterdam where nobody has cars, even if the gas tax is 3X higher. I definitely see your point, it's not easy to directly translate.

Ya you just have to scale by lifestyle factors. If the lifestyle factors are likely to change with location, then you definitely need to account for that with respect to your personal situation.