There are two separate issues in this discussion.
The first one is can you buy kindles from amazon.ca? Evidently you can. But can you buy all models that are available from the U.S. site?
The second issue is can you buy all Amazon digital material in Canada just as easily as if from an American address?
There are some posters saying that there is no problem based on their experience.
The problem is what is their experience. Have they tried buying the digital edition of a U.S. newspaper? A U.S. magazine?
How about technical ebooks? You know, the kind that go for 60 or 80 dollars in the digital format because they have such limited distribution. Did the publishers of that kind of material go to the trouble of dealing with Canada's so called consumer friendly copyright laws?
Is Amazon's cloud storage of purchased ebooks available to Canadians? Their Prime option?
If you haven't considered these kind of issues then you haven't a clue whether there are limitations imposed on Canadian subscribers to Amazon services.
Of course the best sellers are available in Canada. But some readers interests go much further than that.
I am aware of methods that I can use to get a Kindle shipped to me through an American address. But I don't know how to arrange for an American billing address on my credit card.
Gift cards sound good but don't you need a credit card to open an account with Amazon?
Is hiding your I.P. address necessary if Amazon has an American shipping and billing address for you?
Currently I use Google Play to download ebooks on to my tablet because I just can't figure out how to get Amazon to display ebooks only. Since Google Play has ebooks only I don't have to spend time looking at books only to find out there is no digital edition.