Even when this goes through, enforcement of it is still a big factor. As of now, we have signs and whatnot posted all over near the Ambassador Bridge saying how you need your license and all that to gain access into the other country. Maybe 50% of the time do they actually ask for it. The consistency at the borders is a big part of the problem. Those who are going to be annoyed by this new system, are those who have been across the border a million times, and half the time have simply been asked "where have you been" or "where are you headed". Other times, you get these customs people who are quite serious about it and want to see all the ID you can produce on the spot. If every time you crossed over you actually knew you'd have to have license + birth certificate to make it across, carrying a passport would be no biggie whatsoever.

Those who live close enough to consider going over the border just a quick commute......If you're really that close, then you won't mind turning around and spending 5 minutes getting your passport.