I've bought these fares a couple of times as a "back up" fare. For example, when my father was ill and was possibly going to have to cancel a trip to see me, I bought a ticket for around $38 round-trip (with tax) so I could see him instead. However, he recovered enough to keep his planned trip, so I didn't use the ticket. I also once bought a "$9 fare" in case I couldn't get a better flight time & more convenient airline, but then didn't use it because I found a good fare on Southwest. And, I bought one ages ago for a planned trip to LA next month, but now it looks like I'll have to cancel the trip due to illness.
Have I ever actually used one of these $9 fares? Yes -- I had a round-trip ticket from Orlando to Detroit for about $25 with tax, and used the return part of it. I actually had no interest in the "outbound" (Orlando to Detroit) segment, since I live in Detroit, but the cheap fare was only available if you traveled starting in Orlando, not if you were starting in Detroit. (I flew Southwest back to Detroit.)
So, that's something like four round trips I've purchased with these $9 fares (5, actually, because the LA trip was for me and DH, not just me), and so far, I'm used one one-way ticket once.
I've spent a total of maybe $200 with tax on these and have only used a one-way ticket worth maybe $100 tops! However, it was nice to have the flexibility and "insurance" these tickets offered me.
I suspect Spirit is counting on people not using a lot of the tickets. You can't get anything back if you cancel, because they have a $60 change fee (which is more than the cost of the ticket.) Also, the routings are almost always set up so that you can only get the good fare one-way. The Orlando - Detroit routing I did is a good example. Probably plenty of people want to travel Detroit - Orlando in January, but few people want to travel from Orlando to Detroit then. So, Spirit sets up their fares so that the Orlando to Detroit segment is only available at $9, say, from January 5th through January 10th, and the Detroit to Orlando segment is only available at $9 from January 11th through January 15th. Since the $9 fares require a round-trip purchase, a Detroit traveler would be stuck paying the regular fare on the return flight. (Unless you just use half the ticket, and fly another airline back, like I did.)
Also, Spirit has HORRIBLE customer service, packs customers in like sardines, often poorly ventilates their passenger cabins to save on fuel (I'm assuming, or at least hoping
, they ventilate the cockpit
adequately), and nickels-and-dimes you for everything imaginable (including soft drinks), and for a few things that are hardly imaginable. For example, would you and your traveling companion like seats together? That will be extra. Otherwise, Spirit will randomly assign you to seats, probably in different parts of the cabin.
I am serious.
Bottom line, the $9 fares are real, but you have to be creative on routings, have flexible traveling plans, and be willing to except a serious lack of "frills" (like, counting water and adequate oxygen as frills. :annoyed
Generally, I find Southwest to be a MUCH better deal, considering they give free soda & peanuts, free checked luggage, a choice of seats, etc.