Dono makes a good point though.
We always take taxi's at night because we do like to have more than we would if driving in the evening.
However, one of our favorite things is to stop at Corona and snorkel and have 1 beer. Then drive over to Rasta and have 1 beer. Then we go somewhere for a long leisurely lunch with 1 or 2 margaritas. Then switch over to water for the rest of the day. My husband (200 lbs) is not intoxicated, but I wonder what he would ring up as? I would hate not to be able to do that kind of day. This occurs over a time period of 10:30 to 2:30 ish.
I sure see plenty of local ex pats at Coconuts and Woodys having a couple drinks with a meal. Do they all take taxi's?. How about all the people at Buccano's at night?
I am all for stopping drunk driving, but without any kind of reasonable options, the random stopping of vehicles seems a little over the top...................................... of course, if there are indicators then go for it.
Maybe all the bars and restaurants could stock breathalyzers