It varies by jurisdiction, but that's not at all an uncommon restriction in a DWI probation, in my experience. I would suggest to him (or anybody) that how you respond is more important. If he really doesn't have an alcohol problem, that's nothing more than a minor annoyance. Time spent witching about bad luck, or whatever, is time wasted, IMO.
He had to drive only his car with a breathalyzer for four months. No incidents.
But now he may not have any alcohol whether or not an auto is involved Has he been given good legal representation? If this is normal, well, he will have to do.