Investment is investment. Just because the money doesn't go to industries you deem to be "important" doesn't make it any less significant. There are far more Canadians that make a living off of real estate than building cars, and to them a Chinese person investing in Burnaby is pretty significant. Maybe you don't like "condos, resources and energy", but those sectors (specifically) are the only reason Canada isn't duking it out with Latvia and Mexico for "who can assemble a better Malibu" at the moment. And still, Chinese product safety is not a major liability. It needs to be improved, obviously, but you make it sound as if the 100 deaths over the past decade in the US (90% of which were due to parent neglect) is the premier threat facing Canadians. That, literally, hundreds of thousands of Canadians would slip into poverty is of little or no concern. If all Canadians can't have jobs 'working the line', what is the point of trying to earn a living in another field, right? Let's just ban all imports, start fixing prices and maybe we can try to export hockey to Venezuela and Zimbabwe.
You're logic is, in short, free trade doesn't exist ergo why bother. That is very black and white. There are varying degrees of free trade, and you would probably oppose all of them because they don't fit you're Hamiltonian vision of every Canadian working in a factory, driving a GM and living in a nice quiet suburb. It doesn't matter to you that, even failing short of some kind of Ayn Randian economy, country's that liberalize their economies routinely and consistently out perform those that do not. The 20th century is littered with failed autarkies, from Fascist Italy to North Korea and Hawley-Smoot USA. Maybe the greatest example, Japan. Dichotomy's wet dream because they managed to take one of the world's largest growth spree and turn it into a decade long recession just so that they could keep subsidizing their rice crop at 490% of it's value, restricting immigration just to keep shoveling billions into dead end robotics and subsidizing just about every failed concept from the Minidisc to NetDocMo to the Sony Aibo.
What is you're point? That buying "made in China" products is ethical from Walmart, but buying a Prada bag made in China isn't? First of all, Prada, Gucci, Hermes are textbook cases of conspicuous consumption. The utility of a Prada bag isn't that it can carry things, it is that you spent 5k on it. I've never understood conspicuous consumption, but when people buy some of these things they are getting more than just a bag (at least, to them).
More importantly though, so what? Fine, Prada customers are bad shoppers, the owners of Prada get the money and spend it as they please. It is still in the economy, being cycled from air headed heiress shopper to clever high fashion sales men to overpriced coffee barristas, the BMW dealership and the coke dealer. The circle of life. Walmart products having lower margins doesn't change anything (they were low margin in Canada too...). If you think buying foreign goods is wrong, and you shop at Walmart, you are still just as much of a hypocrite as if you bought a Gucci Bag made in Phuket.