Yes, I'd just like to say that the Statistics Act, of course, was passed and is under the control of the Government of Canada, and I see no problem with changing the penalties there for non-compliance. I think the phrase “under threat of imprisonment” is very misplaced in this discussion, since it's never occurred, but “under threat of fine” makes perfect sense.
I park in downtown Ottawa, downtown Toronto, and I also drive at speeds occasionally exceeding 100 kilometres an hour, also under threat of fine. I believe that the value to the Government of Canada, to the society, to the provinces, and to all of the interest groups that have spoken on this debate makes that small price, perhaps a $100 fine—which is in fact consistent with the practice in Australia and with the American community survey, which Professor Tanny brought up—a level that I don't think most Canadians or statisticians would have a problem with.
The word “mandatory” itself says to Canadians: we would like you to fill this out. If, on the other hand, you proceeded with the words “intrusive” and “voluntary”, you are saying to Canadians: don't bother filling this out, because it'll just disturb the rest of your day.