The odds of being struck by lightning are about one in a million in a given year and one in ten thousand over a lifetime. The odds of catching it on video would probably be considerably less. And this guy's reaction to his girlfriend nearly being struck... well... it's also one in a million.
Being president means countless photo opportunities and public appearances, most of them probably ones that one doesn't want to do.
When President Barack Obama was at a polling location in Chicago promoting the midterm general elections and casting his ballot, he probably didn't plan on being threatened by someone about their girlfriend.