There's a point to be made by (sometimes snarky) non-Americans about the stereotypical "dumb, always smiling" American - there are times when it is insincere or

There's a point to be made by (sometimes snarky) non-Americans about the stereotypical "dumb, always smiling" American - there are times when it is insincere or a bit unnecessary and I think that this is unique to America. I also find this stereotype to vary by location - it's more apparent when venturing down South, for example, but less so in a place like NYC. That being said, and this is anecdotal, but I've had experiences from all over the country - I've lived in the Northeast, spent extensive time and have family in the South, etc; a lot of the time people are smiling genuinely or being cheerful with purpose. Most of the time it's not a facade, naivety, or sign of stupidity, as some would like to think. Is it really hard to consider the possibility that Americans just have a more positive attitude? And why is that a bad thing?