AFAIK all of the Low Cost carriers operate the same way... Frontier, Spirit, Allegiant and Southwest have NEVER rebooked on other airlines as a routine measure. Rebooking for free on THEIR next flight, or a refund, those are the choices. .And the relationship ends after that refund. As one commentator said, they aren't going to buy you a "$359 Delta ticket after refunding your $49 Frontier ticket". The risk of booking with those airlines.