More about The Martian Chronicles

"When I was a kid my folks took me to visit Mexico City. I'll always remember the way my father acted--loud and big. And my mother didn't like the people because they were dark and didn't wash enough. And my sister wouldn't talk to most of them." ... "Anything that's strange is no good to the average American. If it doesn't have Chicago plumbing, it's nonsense." [spoken by Jeff Spender in a chapter of The Martian Chronicles entitled "June 2001: And the Moon Still Be As Bright"]

Spender portays his family as close-minded, ignorant and ethnocentric. He goes on to insinuate that his family's actions reflect that of an average American. Does this excerpt truly describe a typical American's attitude toward other cultures?
What do you think?