I recall DL published a stat a few years back about the percentage of awards redeemed for domestic coach (unfortunately, I can't find it anymore). I seem to recall it was in the high 80's. It seems pretty clear that number of flyers who actually save up for J awards or obsess about "maximizing CPM" is actually pretty small and that FT's do not really reflect the typical Skymiles member.
Over 70% of DL's revenue comes from domestic flying, so it wouldn't surprise me that a large amount of awards are domestic too. I certainly agree about the typical Skymiles member. If you don't fly that often, 25,000 miles is just a number in your account while $300 is real money. I'm just saying, even for those who pay attention to things like CPM, the incentive has gone down to maximize. Especially if one doesn't fly internationally.