If I'm willing to accept as little as $60, then I should bid $60. If someone else bids $1000, then I get $1000. I don't do any better by anticipating their bid and inflating my own bid to $999. If they bid $61, I get $61, and because I value not-having-Facebook at $60, that means I get $1 of surplus value.

Anyone bidding higher than their minimum price doesn't fully understand the second-price auction. Probably lots of people don't understand it, which could lead to inflated bids. (but that doesn't mean you, knowing better, should inflate your own bid!)