You can buy one at full retail price through Verizon and keep unlimited, but there's no point in that when you could buy used off eBay/Craigslist and save relative to the $650 off-contract price.
Well, the point for me was less screwing around. My phone was dying while traveling, so I went into the nearest store. They in effect offered me a $400 subsidy if I signed a new 2-year deal and gave up unlimited data. I was happy to pay the full price to avoid that and still walk out with a new phone.