I tell you, you have bad self-confidence and you give me a school class lecture about brain physiognomy. Really..Ehh I'm not sure I really understand why you're associating the issues you have with my perception with Americans as a whole. While I am certainly American, I feel like I am a fairly poor representative of the average American in terms of spirituality, views of psychology, views of personality theories, and overall background and personality.
I do believe the theories are not particularly scientifically valid, but are nevertheless useful tools.
Consider - with the technology we currently have, it is not possible to landscape and categorize the inner workings of our minds in terms of the frequent patterns of cognition we use, but it is evident from shared discussion that we do have patterns that are prominent in certain people and are prominent across certain groups. So it may be in part that technology is just not there yet, but also there is still the mind-body problem to get past. I actually did a literature-based research project tracing the mind-body problem and its history from Descartes to the present, and its implications for neuroscience and other fields. It's a fascinating topic, and one that is still largely unsolved. Where does body end and mind begin, and vice versa? What is the difference? How come we can translate some things but not others? How come we have some degree of influence in either direction but not complete?
As for the States... I don't find there to be much "choked spiritualism" here. I live in the South, where it is more common to find people who are so spiritual that they are willing to completely disregard scientific evidence when it runs up against religious tradition, rather than reconsidering historical beliefs or attempting to integrate the two.