I hope you are wrong this time. This isn't their standard offer. This special offer specifcally says "any paid... flight". The fine print later says the same thing.

Makes sense?

"You have been selected for a special promotion that allows you to earn WorldPerks Elite status fast! Fly on any paid Northwest Airlines®- or Alaska Airlines-operated flight between March 1 and May 31, 2004 and you'll earn points, which can earn you Elite status. You'll be Elite in no time at all!"