Given the value that most popular used hifi products retain, I'm guessing that many people are buying new (or gently used) Ares II's and other DACs for trial purposes, knowing that if it's not their cup of tea, they can easily flip them without losing much.
If I were in the market for a new DAC, I might be inclined scoop up a selection of Denafrips, Schiit, Mytek, Topping, etc that I found on the used market, knowing that I can sell them easily and only be out shipping and paypal fees.