As someone who's had upwards of 30 parcels from the States in the last couple of years. I can speak with some experience. ;)
The idea that we should have to pay GST on imports at all is just a form of protectionism. You know what would stop people importing so much stuff? If the local prices weren't bloody ridiculously high.
One could argue that GST on goods for personal use is just that. For business use it's a totally different issue. GST paid by a business is cancelled out when GST is charged on those goods that are resold. If a company didn't pay GST on those goods there would be a significant exploit in the system.
There is no way to assess whether imported goods are for personal or business use (ie being resold) so the fairest way is to charge GST on all goods. If personal goods were not subject to this businesses would simply rort the system.
Nil Einne: The fact that the person providing the service overseas is not likely to make a difference in their minds if it's effectively being 'consumed' locally, and I doubt the OECD says any different (I'm pretty sure the EU has already convinced most large companies to charge VAT to EU residents even for software or whatever other 'service', wherever the company is located, their large size makes that a lot easier for them of course.)