For the vast majority of Canadians, there's no issue. They have a driver's licence, and that's the single document they need in order to be given a ballot. There are approximately four million eligible voters in Canada who don't have a driver's licence, or an equivalent provincial ID or territorial ID card. That's where they fall into the second group, where they require two pieces of ID. For the vast majority of those, again, it's not a problem. But there are some people, and it's about 1%, who simply don't, in most cases, have the address identification.
If I take my driver's licence out of my wallet, I have no other identification with me that proves my address. I have a whole lot of cards and things that have my name on them. There's a very high mobility rate in Canada. About 13% of people move every year. Companies and organizations don't tend to put addresses on these identity cards, for obvious reasons; they go out of date too quickly.