Music all the time on the plane !

What I honestly enjoyed the most about flying with FlySafair is that, once the plane has reached its height and the seatbelt lights are switched off, I can power up my mp3 music player, put my headphones on and relax until the plane has landed. In fact, I can keep listening to music for as long as I want! I wonder why the other airlines are so uncompromising about this? Surely IATA rules are the same for everyone? But this I really enjoy and appreciate :):):)