For what its worth, a friend of mine had to return early from Florida to Gatwick and was connecting on to Dublin on Ryanair. A similar situation?
He eventually returned home on a BA flight for what he considered a fairly reasonable sum. Just a few hours wait.
Likewise, a friend missed an easyJet flight and having steeled himself for a large disbursement was only charged a "nominal" £25, to get home on the next flight. I could be wrong, but I believe they offered a seat on the last flight at no charge.
Now, which airlines will these guys be considering first for their next flights.
I suppose the moral is that the price of super low flights is subsidised by those that are gouged. No matter how gullible the public may be, they are going to learn that lesson, sooner or later.
