Is it because they can't stand the thought of being unable to make rules the rest of us that they exempt themselves from?
Incorrect. It is because they and their wives are addicted to the Washington DC scene. The power, the lavish parties, the lobbyists they schmooze with. They are addicted to the entire social scene and milieu. Also many money making opportunities for wives (many are lobbyists) and offspring and for Senators and Reps too
They hate the voters, want nothing to do with them. They see voters as an evil they must deal with every 2 or 6 years