Not everyone brings a latop when travelling, or has a laptop with long enough battery life, or would be flying with an aircraft/in a class with in-seat power. And sometimes you just forget stuff - earphones, loading new video files, power adapter....

I fly SQ 99% of the time as it's my company's designated carrier, IFE is not just movies and tv programmes, but tonnes of computer/nintendo games to choose from. Sometimes I just don't feel like dealing with setting up my laptop and wires. And given the selection on SQ, I've enjoyed watching things that I don't normally, like a Japanese movie or travel documentary. I actually got started on House from an episode I caught on the plane. I enjoyed it so much once I landed in HKG I headed over to HMV and bought the Season 1 DVD!

But I wouldn't necessarily only fly with airlines that have good IFE - for personal travel price would be more of an issue.