This is why the feedback system doesn't work. If eBay actually would remove feedback that they decide was given unfairly that would be one thing, but all they do is make it a neutral and add a flag to the users feedback that says "1 negative feedback has been removed."
This still makes people wonder.
Feedback can't be trusted anymore either. I bought a $500 item from somebody with 100% positive feedback and over 1,000 total feedback, only to never receive the item, and find out later that the guy had been the victim of a phishing scam of some sort. Basically his perfect account was stolen and he had hundreds of negatives shortly after. Just goes to show that even 100% positive doesn't mean anything if the person is an idiot and lets their account get stolen.