Built in IFE's are pretty expensive, due to the required certification for each a/c type, periodic checks and fixes, and eventual need to be removed or replaced

Built in IFE's are pretty expensive, due to the required certification for each a/c type, periodic checks and fixes, and eventual need to be removed or replaced. And most of that has to happen with the plane not making money, in a hangar. Then also weight + fuel burn. It seems like a reasonable excuse to me.