I doubt incomes are that different between Canada and the USA. I know lots of people who go on vacation for 2 weeks at a time whether it be camping or WDW.
Maybe it's priorities then? Americans would rather spend their money on other things besides travel? I'd rather spend it on travel personally, but I really don't know many people like me who would rather do that. All of my and dh's family don't 'value' travel the way I do. Maybe because the US is so large and we don't feel like we've really gone anywhere that different from home, whereas in Europe traveling to a different country is so easy and close. Canada though, I don't know, they're huge too, so I guess just cultural differences? I also don't know many Americans who really want to travel outside our country. I really do (and have a little, but not enough). I feel like going to the UK or Germany, etc, would be totally magical. Most people I know don't feel that way. And I don't know why.