As far as eBay is concerned, the service they provide "listing an item for sale through their websites (.com .ca etc)" is done is San Jose, California.
In January 2002 I visited the "War Room" where all the 'stuff' takes place. It was huge then and I can only imagine how huge it is today. The .ca is only an extension and the 'stuff' is on the same servers.
Having back up or mirror servers elsewhere would not legally change the status of the service being provided from sources outsice Canada, hence not taxable.
Foreign ownership has nothing to do with GST/HST. It is strictly where is the service provided. These things are highly technical.
For example, did you know that if you are located in Ontario and you ship a parcel to a buyer in New Brunswick by regular parcel post, Canada Post will charge you 5% GST at time of purchasing the postage.
If you ship the same parcel to the same buyer through the same Canada Post outlet in Ontario but shipping by Priority Post or Purolator, you will be charged 13% HST.
That is the law. It is based on technicalities involving "bill of lading".
Want to beat the system? Purchase postage stamps, pay 5% GST and lick them to the parcel!
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