Okay, if the point of being a Jedi is to surpress all passion, fine. Okay. Sure, even Vulcans get to cut loose once every seven years, but I suppose having an insanely calm ruling class is probably good for the social order. You wanna live an ascetic monastic life? Hey, knock yourself out.
And so then the point of being a Sith is thus to let your passions run wild, draw strength from them, destroy your enemies, etc. Okay. Fine.
Then how come you go to a Sith academy and lo and behold, everybody's got metal underwear and a single bed? (Yes, I looked.) You get beaten like a bloody flagellent and fed to starving monsters and tortured on weekends. You slog through your training, achieve a sufficiently high GPA, and get to be a Sith Lord, and what do you do? You stalk around on the bridge of your bigass starship, brooding, and glare out at empty space wishing you could bitch-slap the entire galaxy simultaneously. (They all do it. "Here's your diploma, congratulations, here's the keys to your star destroyer...") They don't even get a comfy easy chair to brood in. They all gotta stand up or else levitate in lotus position.
Do you get regular massages? No! Do you have legions of hot alien women waiting on you hand and foot? No! (You get one apprentice, who will always try to kill you, and will usually dress like a freak and wear too much eye makeup in the meantime.) Do you at least get good food? Possibly, but always off camera! Do you get to sleep in late? No, because other Sith will use the extra hours in the day to take your starship so that they can brood on it instead!
What's the fun of giving in to your unbridled passions if they're such LAME passions!? I mean my god! A pack of Catholic high school girls could cut looser than the Sith! If you're going to be evil, why aren't you people ever having any fun!?
George Lucas just doesn't understand human nature worth crap.