"Say, we need to show we're diversified. Could you just Photoshop one of them dark people into that picture of a white family? That'd be great!"
I have a fairly easy test to see if any of the children's books my girls read are worth a shit or not. If the main character goes to a school / has a party / is playing with / or any combination of where there is a perfectly even mix of races, genders, and at least one handicapped kid in a wheelchair, you know the book is going to be preachy and full of suck.
Oh, the "non-homogenous friend" rule is null and void if the main character is a minority. Then there's less diversity than a Klan meeting.