Frequent-flyer miles are no more pyramid schemes than are national currencies. All currencies lose value over time (inflation). The key difference with FF miles is that we can't invest them so they appreciate -- they're all stuffed under our respective mattresses. So it is dumb to hoard them.

With the definite exception of Continental, which markets "standard" awards to hot destinations like Europe that are in practice virtually unavailable, it is not that difficult to redeem miles if you're flexible. The people who seem most upset about being unable to redeem FF miles usually went after two first class seats to Hawaii the week before Christmas, a week before the departure date, etc. and were as you might expect disappointed.