It's a dirty money-grab, but almost all countries have something similar. Not every country has the high-way robbery rates you mentioned though.

Both the Canada and US also tax imports for private citizens. It doesn't matter that there also exists a couple of free trade agreements between the two countries. That agreement doesn't affect the taxing, only import duties and a few other charges.

When I bring anything in from the US as a private citizen into Canada, regardless of the value, I will have to pay 5% federal tax (called the Goods and Services tax - this used to be 7% two years ago) and 8% Provincial tax for Ontario. In other provinces the provincial tax amount is different - example, it's 0 in Alberta. This much is fair on new items purchased from a store, because it's the same amount of tax you pay at any store here locally.

Packages under $20 usually get by without having to pay anything because they don't want to be bothered collecting such small amounts. But not always. Sometimes packages with higher values slip through as well. In addition to the tax we will also pay a surcharge to the carrier for collecting or processing it. $5 to Canada Post for low-dollar collections with it going up to $15 for much higher amounts. UPS will charge anywhere from $15 to $50 and I don't know how they calculate this "brokerage fee." They once wanted me to pay a $37 brokerage for an $8 magazine they were delivering. UPS express shipments have lower brokerage fees. FedEx charges about $7 for the same thing on express and about $15 on non-express (ground).

In Canada we are supposed to declare all private non-store purchases of all goods, new and used for the purposes of submitting tax. For instance if I bought something from someone in another province over the net it doesn't pass through any borders or customs, therefore I don't pay anything. I'm supposed to declare that however so that I can pay both the GST (in most cases) and definitely the PST. Even buying something used from someone within my own province. I'm supposed to pay tax on it. I've never heard of anyone actually doing this of course.

On imports this applies to both purchases and gifts.