Flying is still pretty incredible. They just need to try to make the plane more comfortable and enjoyable...hence the hotties.
If they made the plane more comfortable, fewer passengers would fit, and the airline would (potentially) have lower profits.
On the other hand, it doesn't cost any more to pay a pretty young stewardess than a homely middle-aged one ... less, in fact, because their union makes pay based on seniority.
My ex-sister-in-law was a USAir flight attendant, until they cut back after 9-11. You'd have admired her, I think.