Let's take burglary. Let's imagine a nineteen-year-old down on his luck, driving a hooptie with a broken fuel gauge, because that's all he can afford. He runs out of fuel and his car is stuck on the street in a suburban neighborhood far from the nearest services. He doesn't have a mobile phone. He walks around and notice a car parked on the street and he siphons enough gas from the tank to make it to the gas station. He gets into the car and suddenly a police car comes in behind him, arrests him for Burglary of a Motor Vehicle, so now he has to pay a 2500 dollar fine and spend six months in a penetentiary. Does the sentence seem to fit the crime?
No. But that's a red herring. If someone burglarized your residence, clean wiped you out of your possessions...really no prison for that? Or are you arguing that burglary should not automatically mean prison?
Or what about conspiracy? There's a holiday song that says, "Later on we'll conspire, as we dream by the fire, to face unafraid the plans that we made, walking in a winter wonderland..." Prison for this?
No.
As for drunk driving, it's currently a misdemeanor. At least for the first few offenses. You get a heavy fine as it is, and your insurance premium increases, but does it merit imprisonment?
Yes. A strong deterrent effect is needed. People's lives are at risk when someone drives drunk.
The Navajo had a cure ceremony for those afflicted with maladies. If you got drunk and shot up a store and stole something, it meant that something inside you wasn't right, and a wise man would be called to have a sing for you. I'm not sure that stuff works, but I'm quite sure that putting young men in prison only makes them jaded, tough, and wiser in the ways of crime. You don't turn criminals into citizens by treating them the way we do.
It's an interesting point but I think largely irrelevant to whether or not we should put people in prison for serious crimes. If they offend again, put them in prison again, and for longer. Perhaps the prisons need to become a LOT better, but even if they don't we still need to make use of them.