Dumbest Reason to be Stuck in Traffic

I was stuck in sluggish traffic on my way up to San Ramon for about half an hour today. I just assumed there was a stalled vehicle, minor accident, you know, the norm. Didn't really spend any time thinking about it. As I was approaching the Sheridan exit, I noticed three people standing at the overpass waving to all the commuters below. My initial thought was that they were pretty amusing, a good break from the frustration that's built up in the past half hour, until things started speeding up right after I drove under the overpass. I couldn't believe they were the reason for the traffic jam! Three stupid adults waving to drivers below could cause such a hectic drive. I saw two motorcycle cops whiz by as I approached them. I hope those people got a beat down! Just kidding. I do not condone violence... for the most part. :)