For those resident in the UK (and possibly elsewhere), isn't there a tax implication? I'm sure that if my employer provided free air travel, or even gave me a free bus pass to commute from home to my normal place of work, the Inland Revenue would be in touch to get their share of a taxable benefit. On the other side of that, if my local airport was designated my normal place of work and I drove there at my own expense before my employer flew me elsewhere, that would be tax free but for flight crew it would fall foul of the FTL rules.
Or there is sensible arrangement with the authorities that cater for the special circumstances involving airlines, airplanes, pilots, ships, crew, 1000 km commutes, etc. Like there are many many many sensible arrangements with the authorities in every other sector.