I think I would still file a complaint through eBay. If the seller didn't do anything wrong, he might be willing to file a complaint about your post office. He might also be able to prove that he had nothing to do with what happened and that would strengthen your complaint against your post office. There is strength in numbers so it's a good idea to get as many people with complaints as you can.
He already got his money back, so I doubt he'd want to deal with any more hassle than he already has. These corrupted activities don't seem to be very unusual though. I myself have received a few packages that clearly were opened by someone with his/her finger to have a peak at what was inside. Luckily most sellers are aware of this and either add enough bubble wrap or another package inside the package (packageception). It's up to the seller to get his money back now, I have no idea how things work there in China though. But all the bureaucracy could be pointless.
I think it's particularly interesting that whoever it was called you an oligarch when you were buying a cell phone through ebay, presumably to save money.
Yes, I suppose so. Someone has to suffer the brunt of the loss and it might well be the seller in most cases, unless, of course, the seller stakes a claim with your local post office.. in all probability, the theft seems to have happened there...not at source (i.e., China). I've dealt with, and purchased, quite a few items from China and I've never faced this sort of scam. If at all, the sellers from there are very particular about maintaining a high positive feedback rating.
LOL, good point (although, this didn't happen to me, but to a friend of mine). There's currently a huge political debate here over imported things. The government is presumably "trying to defend our country's national industry" by increasing taxes on imported products. Problem is... there's no national industry to defend. And any product you can get in a local store here costs at least 2 times more than it does on eBay; even with taxes applied.