Been there, done that....it is simply b@stardry, dressed up as business acumen, and inevitably ends in pain (think Monarch or Seaview).
Unsustainable in any logical sense, but the continuous cycling of this sort of thing means an unrealistic expectation is held by the clientele, most of whom know dot about aviation.
In my PERSONAL experience, undercut service delivery in combination with obvious F&D breaches, with very junior CPLs (who know no better) being educated that 'this is how it's done....', and clients who then expect it that way. (look to your east about 90 odd nm mornos....)
The wheel turns and those who play this game will eventually get caught out, either by CASA or by the Tax man(before), or by ATSB (after). Unfortunately, plenty get hurt in the process before the inevitable.