Not to be a jerk...
So, if my 6th grader said "Growing up as a bastard child is for black people"...Do you think my kid would be branded a racist???
The two statement aren't equivalent: getting married is a good thing, being born out of wedlock is a bad thing. The equivalent to the children's statement would be "Playing basketball is for black people". Racist and stereotypical yes, but hardly a big deal in either case.
Frankly, I am more concerned with why a large number of black children think marriage isn't for them than someone who would get offended by being labelled as the marrying type.