Pabely, you might want to get to your destination as quickly as possible but there are many including the relatively well off that are happy to take a long transfer as it gives the chance to see someone new and somewhere you may not otherwise be bothered about travelling to specifically. For us Brits and other Europeans probably the best examples are Doha, Dubai and Abu Dhabi, eg Qatar lay on specific coach trips defending on how many hours you're there.
I agree that for us Brits a long stop in Iceland may be a bit of a nuisance, as it's not that far and we're able to travel there pretty easily. But put yourself in the shoes of Mr and Mrs American coming over for a two week tour of Europe. The chance to see a bit of Iceland is quite exciting.