Same as in every place of the world we live in, some people in US are very nice. They are simple nice. I definitely know some of this kind. Especially those parents whom the above artical mentioned.
But there are others, perhaps not worth to mention here. I know one or two...in China, all his friends (or her) friends took trouble to help him (or her). But when his (or her) Chinese friends went to US and met him (or her), who wasn't even nice to treat them a decent meal. It is not he (or she) was too poor to do so.