Interesting observation, but the one that is to be expected. PayPal, just like ALL other financial institutions that serve as the "middle man" for you and your money, will always play on foreign exchange and make extra money on it. With all my experience with banking institutions worldwide, they are all the same everywhere.
As far as the US dollar goes, I don't know where its all going... but I don't like it. I don't like it at all. The American dollar loses value and they still spending left and right on war action. Actually, that's one more reason why they (most likely) will never bomb Iran. The economy is in grave condition. Expensive wars, housing market decline, medicare, the mortgage debt... American financial liquidity is scary low. Will those additional candy-rides finish America as we know it?
Best,