50% sounds high but then again there are lots of people who just don't fly that much and may not see the need, or value, in collecting miles or building loyalty. I know that's a horrifying thought for many of you.

On the other hand, I have FF accounts w 2 airlines that have a zero balance. I signed up w AirTran a few months ago only so that I could log in at T-24 to choose seats vs. paying in advance. That flight was on a promo voucher that didn't earn miles and was maybe the 5th time I've ever flown AirTran over 15+ years. I also have a FF account w AA w zero balance - signed up years ago when I thought I was going to have an Int'l business trip on AA but the trip never panned out.