But it may not just be out of disrespect, turns out Bush is actually a clean freak. Obama describes meeting Bush for the first time in his book "Audacity of Hope":
“Obama!” he said, shaking my hand. “Come here and meet Laura. Laura, you remember Obama. We saw him on TV during election night. Beautiful family. And that wife of yours – that’s one impressive lady.”
“We both got better than we deserve, Mr. President,” I said, shaking the First Lady’s hand and hoping that I’d wiped any crumbs off my face.
The president turned to an aide nearby, who squirted a big dollop of hand sanitizer in the president’s hand.
“Want some?” the president asked. “Good stuff. Keeps you from getting colds.” Not wanting to seem unhygienic, I took a squirt.
On second thought, it might just have been out of disrespect both times....