The combination of sporting finals and hugely popular Aggies Race Day would have kept police busy as there is no doubt that, despite decades of warnings, some people would still take the risk and drink and drive.

According to the Centre for Road Safety, drink driving is a factor in about one in every seven fatal crashes in NSW.

Of the drink drivers and riders who were killed in the five-year period from 2013 to 2017, 93 per cent were men and 67 per cent were under the age of 40.

Random breath testing has been part of our lives since 1982. Since then, according to the centre's statistics, trauma from fatal crashes involving alcohol has dropped from about 40 per cent of all fatalities to the 2017 level of 15 per cent.

Police conduct about five million breath tests each year in NSW.

It's clear that random breath testing has had an enormous positive impact on the road toll.

But, given that it's been part of our lives for almost 40 years now, you have to ask why people continue to run the risk by drinking and then driving.

It's not just the increased risk of crashing, but also the ignominy of - if you are over the limit - being arrested and having to face a court hearing.

In NSW, drink driving is a criminal offence, so not only do offenders face the likelihood of a fine and being disqualified from driving, but they will also have a criminal record.

Why do it? Why run the risk of fines, or even a jail term, a criminal record and the massive inconvenience that could come with being unable to drive?

When weighing up the risks, one question many people should ask themselves before starting the car is whether they'd still be able to get to work - and indeed still have a job - without a licence.

We've been hearing it for years, but the message is still true: If you drink and drive, you really are an absolute bloody idiot.