Very difficult to choose the first one, but I'm going with something that affects me almost every day:

"Oh, look, George, thank goodness!  There's an Applebees over there," says Judy as her and her sweatshirt-clad brood of 6 cease all movement smack in the middle of the sidewalk during rush hour.   In the human version of a highway pile-up, those who can't swerve in time must also come to a grinding halt or risk colliding against an admittedly probably fairly padded mass of near-humanity.  You're making me 2-5 seconds later to the gym, people!  What's a gym?  Gah!