said by Guspaz:
One difference is that we have to pay full sales tax, while the Americans don't (no tax on internet purchases in the US)
Entirely incorrect. I order stuff from the US Amazon.com all the time (in fact, I just did yesterday) and have it shipped to an address in Niagara Falls, NY. I pay the 8% NYS/Niagara County combined sales tax on my purchases.
The US is the same situation as Canada - it entirely depends on where you're having it shipped to and whether or not the company has registered for sales tax collection in the jurisdiction of the destination address. Some American states take it a step further, and insist that *you* pay the sales tax on out-of-state (including Internet) purchases you made, and include it on your tax return. Not an issue for us, but can be for the people who live there.
So, if anyone is thinking of ordering something from US Amazon and having it shipped to an address in NYS expecting to not pay sales tax on the US side, you're out of luck.