Interesting! It may be a geographical thing. Clearly they don't want you to be able to do a free "circular commute" so for instance, in the Bay Area, all bridges charge toward San Francisco, and are free in the opposite direction. So there's no way to do a circular commute that wouldn't add 100+ miles by circumnavigating the Bay every day. But it seems like it "should" be simple enough (Dangerous words!) to coordinate say, "all bridges over a river in the metro area charge eastbound."

It seems kind of a waste from my perspective to have to do the traffic bottleneck in two directions.