Unfortunately lessons we learned on how to conserve gas in the 70's have been long forgotten. The buzzword now is "delays waste gas." So therefore being delayed by a cyclist wastes gas and is bad for the environment.
I'm not disagreeing with the positive side of higher gas prices but it also creates a negative side where motorists want to move as fast as possible (no delays = traveling fast) so there is a trend to drive faster and be less tolerant of things that slow motoring down.