Thanks for the information. This is still only in certain places (I notice you mention tourist destinations--yes, that's the kind of place I would expect this to be done), not "everywhere", and it certainly doesn't mean that you or I as sober drivers can relax and believe that we are not still at risk from other drivers possibly being drunk. But I agree it does go beyond only enforcing the laws when someone has already made a mistake (unless you count "driving into a visible DUI checkpoint when you know you're drunk" as a mistake).