Another perspective - what if they just followed cars leaving those bars and clubs for 1 mi., then returning and starting over after observing the driver's behavior?

I'm actually not opposed to breathalyzers inside of the car - it seems far less invasive than cops doing it for you, with the authority to ruin your life. If the car won't let you drive, call a friend or a taxi.

In any event, I'd prefer to avoid the hassle and feeling of being a suspected criminal that accompanies being stopped on the way home at a checkpoint. Papers please? (jk...?)