My understanding is that one of the main differences is that Canada is a loser-pays environment, whereas the United States is not. What that means is that enormous amounts of money can be made by showering people with spurious lawsuits, because they'll often back out.
I believe one of the situations that happened was in Nevada. A legal firm had gone to a prison and got the people in the prison to say they were subrogating all their private right of action rights, in terms of spam, to this legal firm. Then, with every email they got, the legal firm was making enormous amounts of money suing people. As I understand it, that can't happen here.