Immigrants also have to restart from scratch. Everything in Canada is completely different from what we're used to in our countries of origin. Often, parents who were engineers in their home countries have to work blue collar jobs to make ends meet.
I think the actual difference is in average IQ and other desirable traits like industriousness.
Immigrants tend to be at the higher end while refugees tend to be at the lower end.
Why would people fleeing war zones be on average less industrious or less intelligent? That doesn't make any sense.
However, being a refugee means going through a much more traumatic process than being an immigrant. You are literally thrown from your home with little left and have gone through a difficult process to get out and resettled in a new country. So drug abuse, gang activity, crime, not doing well in school, depression, etc...were problems for that community even though given normal circumstances they would have been similar to other Chinese immigrants.
I'm not sure about your explanation though. Chinese people are not magical people. IQ is still distributed on a bell curve in China as well. If a chunk of people from a country exhibit characteristics that indicate they might be on the lower end of the bell curve, they might just be on the lower end.
This is very different from US where you have a green card lottery and your typical immigrant is just an average population because everyone has the same chance of winning lottery, it doesn't matter if you are a farmer or aircraft engineer.
The refugee system in Canada is frequently abused. I hear anecdotes from my friends about kids from rich families in safe Easter European countries, that pay thousands to immigration lawyers and apply for refugee status simply because the partied too much and didn't manage to get enough points to go through the point based system. Such "refugees" can be safely compared with immigrants.
