At the risk of being less than transparent (but not in the mood for an internet shitstorm), I'm not linking to the comment, nor the blog where I found it, but it's not the first, nor will it probably be the last. Apparently, one of the hallmarks of progressive parenting is teaching your children diversity by sending them to "rough" (i.e. working class) neighborhoods to play. Neighborhoods like the one in which I grew up.
To mingle with the unwashed masses.
Nope sorry, you don't a "good liberal" cookie for this. I am not your cultural enrichment.