The problem is that the data shows it doesn't work. The data shows that in making it voluntary, you can knock at the door, you can be really nice, but the vulnerable people will not respond for lots of different reasons, which probably are not understood yet. Whether they're trying to put their child to bed, working two jobs, feeling socially isolated, or whether they don't like the government, the data shows, and other voluntary surveys indicate, that it doesn't work.
I would love it if taxes were voluntary, but they're not. It's just considered a simple responsibility. You report your income and pay taxes on it.
What I read showed that Statistics Canada got 25 to 30 complaints a year. I don't think that's significant in a population of 33 million people, and I, frankly, as a taxpayer and a citizen, would be very disturbed to see a government driving policy based on 25 to 30 people out of 33 million. I don't think that's good strategy.
So I love carrots, but I don't think it has to be heavy stick--but it's a stick.