I think this goes a little bit too far for a few reasons:

1) Other people who use your PC can get items posted to your Facebook feed - just imagine "Mike Volpe just bought a miracle bra from Victoria's Secret" getting posted to my Facebook feed if my wife used my PC to buy something... scary.

2) Facebook is making money off of me, using my personal recommendations, without my explicit consent, and I don't get a dime.  Why not cut me in on an affiliate program if you are using my name and face to sell something?

Great explanation and discussion:
http://blogs.forrester.com/charleneli/2007/11/close-encounter.html