Maybe so, but I think the deals that are highlighted on DDF are for extravagant hotels that a normal person wouldn't spend the money on.
For example, in Yehudas post he talks about staying in a hotel room that would normally cost him $1,000. I don't know what value he got and what points he was using but for arguments sake let's say the points were worth 1.4 on the open market and he got 4.0 by spending it on the hotel. So he spent 25,000 points which on the open market is worth $350. I wouldn't pay $350 for a hotel room - would rather go to a nice clean hilton for $200 and pocket the extra $150 per night.