If the nominal price is $x at the start and needs to drop to 0 before it'll sell, then the seller can artificially sell at a price higher than $x, by simply putting his own money $n into sale, so in this case the sale happens after the seller lets the total value drop to zero, at which point purchasers have paid $x+$n and the seller has also "paid" $n. However, as the seller is paying that $n to himself, that hasn't cost him anything, but he still nets $x+$n from the paying customers rather than the $x it was presented as.

The seller can do this as long as they like if there is no bound on the auction time, he can e.g. roughly match contributions to keep the price above 0 and at the point it seems like people are losing interest and no more bids are likely, he can then "pay" the difference himself to force the sale through (remember, he'll get this back anyway).

There's even a third option - on a time limited auction, maybe the money raised is already higher than they think they'd ever realistically get if the auction was repeated, or sold elsewhere, but still not at the $x threshold, the seller can just pay the difference, knowing they'll get it all back themselves anyway.

In every case, the seller is in complete control of when, or even if, the sale actually happens and for any price they want, regardless of the originally advertised price. There is no scenario where allowing people to bid to reduce the cumulative value of the auction (your "haters") can ever be fair on the other bidders (your "lovers").