[FridayoLeary]

oddly enough some of my ebay orders also come in prime packaging. On that note ebay is a far better shopping experience at least for anything small.

[bombcar]

There's an entire Amazon fulfillment business that many don't know about - if you move enough merchandise with them you get the ability to use their shipping network, which can be pretty darn cheap.

So often it's the company/seller using Amazon for fulfillment; but sometimes it's just someone doing arbitrage between Amazon and eBay.