you can move to europe, buy real estate easily and live above the local's means because US income is so much higher. In fact thousands of americans are doing it in the past few years

EDIT: Also, a large part of "quality of life" has more to do with the structure of european country populations. They are old , cohesive and mostly conformist societies that tend to help each other in times of need, something that the US, which is individualistic country made of immigrants can never do. This creates a more safe environment to live, but it is not an excuse for lackluster economic performance.