You just have to shake your head, laugh a little and not say a darn word.
I was at my nearby LBS on Saturday, buying odds and ends that I believed I needed after the morning ride. I am in line when I was asked about the Worlds in Madrid (one of the shop clerks). I made a remark about Boonen and a couple of others when the guy behind me says, "Boonen, what kind of name is that"? I replied, "Tom Boonen, he's Belgian." The bloke looks straight at me, without a hint of jest in his voice or eyes and asks, "the Belgians don't do much bicycle racing, do they"?
I politely said, "Umm, I think they race a little." He says, " You don't say." It was pandamonium behind the counter, but only a few knew why.
Enjoy that this week!