Look. I honestly believe that yes, there are lingering vestiges of racism in our society. You don't exorcise something that pervasive in modern culture in less than a century. Occasionally - not regularly, but occasionally - we've all been known to make varying assumptions about other people based on existing stereotypes.
I have no doubt that, in their lifetimes, the Obamas have experienced lots of instances of discrimination based on skin color, and I think that's a tragedy. However, I do not think being asked to reach something on a high shelf at a big box retail store is one of those instances.
"I tell this story – I mean, even as the first lady – during that wonderfully publicized trip I took to Target, not highly disguised, the only person who came up to me in the store was a woman who asked me to help her take something off a shelf. Because she didn't see me as the first lady, she saw me as someone who could help her. Those kinds of things happen in life. So it isn't anything new," Michelle Obama, who is 5'11", said.