Yes, when kids drink underage their parents should be punished, because it is usually the parents who allow the kids to drink. Most parents just don't understand that underage drinking is wrong. They need to understand that they are endangering their own children by allowing it. Parents would try harder to prevent it if they were punished, too.
When kids drink underage their parents should be punished. No parent should allow an underage child to drink it is against the law and if they are helping them to be more active in their drinking then they to should be punished for doing so. It is not right they are teaching them to break the law.
What if the kid was drugged and then decided to drink? The parents cannot account for every single thing. If someone steals the kid and forces them to take a drink while they are asleep? When the kid wakes up, they become drunk, and no one knows until they take a drug test and blame the parent. Not the fault of the parent
When a kid goes and drinks alcohol underage, the parents are usually not involved. Nine times out of ten the kids hide the consumption from their parents. The parents cannot be responsible to teenage kids sneaking around drinking alcohol. If it's in their own house or the children are below the age of 13, there are likely more complicated issues at hand and the parents could be dealt some of the blame.
I do not believe parents should be punished when their children drink underage. This can happen in two different scenarios. In one scenario the parents allow their children to drink while underage. This is very common with teens and those just under the drinking age. The other circumstance may have a parent that disapproves, but the child sneaks it. Parents shouldn't be punished when their children are undermining them and they shouldn't be punished for making responsible choices.