Originally Posted by
East_and_West
That was my first thought when I read OP's question. I would be really interested to know if there is such an airline. Perhaps some airline in the Middle East? As far as I know at least none of the ME3 carriers does this (unless I have missed that).
I know Xiamen offers transfer benefits when you have a extended layover in one of their hubs (Xiamen or Fuzhou). If you have a 2+ hour layover you get free lounge access, if you have a 4+ hour layover you can take a free city tour, and if you have a 6+ hour layover they will put you up in a hotel (subject to double occupancy). They do this for anyone except
G/Z/X/O/E fare codes. Which includes several economy fares including discount economy. I always thought this was a pretty awesome benefit.