In my view, the reason for abstaining from drinking and driving matters not. Whatever is enough to motivate people is good enough for me.
The problem is the real hard-core drunks, IMO - they think they're invincible and can drive just fine. Back in the day (we're talking late 80s, here) one of my colleagues would actually brag that he drove better drunk than sober - and he did it consistently.
Never got caught, either. There, but for the grace of God, as the saying goes.