"I'm not sure if you can blame everything on the American way of life, but the United States are big. So, if you have a lot of people there, the percentage of stupid people is bound to be higher"

This quote by Stephen Malkmus suggests that the large size of the United States implies that the portion of "dumb people" is most likely to be higher than in other countries. He is not recommending that the American way of life is to blame for this, but rather that the sheer variety of people in the United States indicates that the percentage of individuals who are not as intelligent is likely to be higher. He is likewise recommending that this is not necessarily a bad thing, as it is just an outcome of the size of the population. Ultimately, he is suggesting that the US is a large and diverse country, and that this variety ought to be commemorated, instead of blamed.