The thing most non-industry buddy-pass flyers don't understand is that the non-rev system is tiered with some airlines. So just because they've been stuck there for 6 days does not mean they will ever get any closer to the top of the list. At the airline I used to work for, it was NR-5, NR-6, NR-7 and NR-8. Within each category, the traveler is selected by the company seniority. NR-5 were traveling on company business. NR-6 were the retirees (this has since changed). NR-7 were active employees. NR-8 were buddy passes. So if you are an NR-8 and your friend's seniority number is August 2011, you are pretty much at the bottom of the NR-8 list. And even if you've been there waiting for a flight every day for a month, anybody who is a NR-7 and shows up is always going to be ahead of you.
And Salt Lake is horrible to pass ride out of... so many employee commuters live there and everyone has a huge family with 6 children.
And one other thing I didn’t mention... if they knew how to work the system, they would have tried to get to a different airport, like to the West Coast or Denver or somewhere that they had more options. I once had to fly to Brussels to get to London before I could get to Berlin because the DC to London flight was cancelled. You have to be creative.