TartinTon Loganair's schedule ops don't even break even. Even with expensive airfares, it's not like they're making a fortune, they get by and turn a profit when charters and cargo get thrown in. I believe it's a 3% margin.
They're so expensive because they fly prop aircraft on high frequency shedules to the Highlands and Islands and the regions, if they do too well on volume, Ryanair or easyJet swoop in and Loganair depart, but frequency falls to about one daily. Flybe had low fares and high costs and went bust twice. Loganair have high cost and high fares and are celebrating 60 years of (almost but not quiet, thank you British Regional Airlines) continuous operations.