In most cases, the slow poke is gonna cause a collective increase in gas consumption when he tries to do the 'honorable thing' and drives 20 mph off the current popular speed on the Interstate.
I'm not saying the speeders are right, but in this case, the slow pokes better not be going to bed, content that they've saved the environment. Those who disrupt existing traffic patterns are fools and a menace to others, whether they drive crazy fast, crazy slow, or just plain crazy.
Amazing that the slow pokes are the dead last person to use
www.aaa.com and other mapping sources (challenge the info you get, aaa software makes stupid choices one quarter of the time) to discover a quiet and relaxing back way to go; with no schools, no speed traps, and no shift changes at factories (or at the catholic church). 30 miles shorter in trip distance, you save twice by going slower on secondary roads and getting there before the speeders who are fixated on using the interstate.