Ok, it's not racist, but it doesn't help you learn anything, either. It's not funny, it's not interesting. WHY is it there?
And talking about whether a language book should teach just the language:
Why does every American standardized test include a text about feminists and about black people?! And why are correct answers ALWAYS positive towards these groups of people? I mean - is my English bad because I think that feminism is stupid? Or because I don't find it amusing to read texts trying to make me feel guilty for something that was done 6000 km away from the place where I live while actually my own people was massacred by one of the closest allies of the US - Turkey?
And this is not a textbook - it's a test, for which I pay and which is decisive for my future. Cool. :P