Promotion as in the cost was only $600, but you'd have to buy the flights through the promotion company (at a normal flight price). Where they made the money was your spending when you got to the destination.
Mind you we always had to charge the taxes and stuff, and if she didn't mention taxes maybe it was just a normal scammer like ken0042 said.
Heh, one year I remember going to a show at the roundup centre and putting my business card into every one of the "enter for a free trip" things.. I won about 4 trips to vegas and 6 cruises within a few weeks.