Many "grown-up" countries do care about this. This problem is non-existant in Austria, or Germany for the most part. Roadside police checks consist of decibel metering, which they are trained to use. They will impound the vehicle on the spot if its over the legal limit. Even race tracks have strict sound limits, the scrutineering process has a sound measurement part.
I can tell you this problem does exist(and is getting worse) in germany, and it's terrible. Calling the cops doesn't help, because they really don't care, I mean they even don't care anymore if cars are parking on the sidewalk. I live in a small "town" of around 10.000 people, I really can't imagine how bad it must be in bigger citys.
