No, here's the deal.
There is really a lot of drunk driving. I mean a whole lot. After 2:00 AM, half of the drivers are legally drunk. However, it takes a cop about an hour to dispose of a drunk driver. Do the math.
In a city of 200,000, there are 20 patrol cars working traffic beats at 2:00 AM.
Chances of getting caught drunk driving are very small. Only alcoholics that fall asleep at the wheel, run into something, or are really obvious in front of the cop get stopped.
People with DUI's report that they drove drunk hundreds of times without being stopped. If you violate the law hundreds of times and only got caught once and paid a $300 fine, and had a work only suspension for 6 months would that work?
Been on an interstate highway lately? Most every driver violates the speeding laws several times a day there, probably 50 million cases a day. Let's lock them all up, even though they are not a real danger, except for a few extreme cases.