Is consumption defined as spending, though? If an apple costs $1 in the US but 25 cents in Europe, and a poor person in each place is provided a free apple by the government, did the poor person in the US have 4 times the consumption?
Well, you try to adjust by Purchasing Power Parity. That works well for things where you can directly compare, like the price of an apple. However, it doesn't work so well for other goods and services, e.g. single payer health care vs health care costs in the US, because at best you're comparing apples to oranges.
On top of that, it does not account for things you may need in one nation but not in another. E.g. cars spring to mind. In the US you need a car in most places even the bigger cities, to get to work for example. In a lot of places in the EU you don't.
Having a car and being able to drive it around is a form of wealth. Cars in the US are also much more affordable.
The "I don't need it" argument only goes so far. You can't go shop a lot of groceries. You can't transport bigger items. You can't go on a road trip. You travel according to whatever public transport affords you.
I might just as well say "I don't need it" in regards to healthcare. You don't need it until you do, but then you can't afford it.
