Perhaps what he meant was that they have never given out tickets and towed cars before any snow fell.

That might well be the case. Maybe in the past the city has "declared" the emergency before snow starts coming down, but just didn't take any actions to enforce it. They started aggressively towing for street cleaning last fall, too. It used to be just a ticket, now it's a trip to Pat's Tow. Definitely a revenue-enhancement decision.