There are way to punish besides locking them up. Make them pay into a victim of drunk driver fund each month. Each month they miss a payment, the monthly amount owed each month increases.
Miss repetitive months start seizing cars, truck and other properties to sell at public auction. Letting an individual lay around on his arse while the tax payers pay his/her medical and dental, clothing, food, foot ware, and college education is not in my mind punishment. The kicker being providing a guard 24/7 to insure the SOB’s like minded friends don’t do him/her personal harm.