In addition, drunk driving is a relatively controlled problem. That is, a relatively small percentage of the population do it and law enforcement is able to police it with a reasonable degree of success. On the other hand, it we had an epidemic of drunk driving where say 20% of the people on the road were driving drunk then it very well may make sense for the government to barricade the roads until they got things under control.
Edit: Found this as a support source, while not 20% roughly 2x the rate in rural vs urban areas https://www.ncbi.nlm.nih.gov/pubmed/30160320
And yet you argue that allowing free commerce in America is not okay with a population that is dangerous to a relatively small percentage of the population.