My pet peeve expands on yours.... A line of tailgaters all following a slow moving vehicle, and none of them make any attempt at a passing no matter no but they since they are all tailgating, nobody can pass without PASSING THE ENTIRE LINE AT ONCE.
Of course, when a 2-lane passing zone finally comes up, the slow guy up front never fails to speed up well beyond the speed limit, only to slow way down again once it merges, with all his tailgating minions still on his bumper.
This is the reason I turned off the 100 MPH governor on the my van.
I also really like it (not) when I'm in a truck and use a pullover to let traffic by, only to get stuck behind one of the cars that was just moments before tailgating me, and now I'm stuck going 10 MPH slower. Its like some drivers have zero concept of speed, and must have an anxiety attack when there isn't a vehicle in front of them blocking their view. Makes me wonder if they can't even see the lines lines, and they have to follow so close so they don't lose track of where the road is.