Another one would be that on modern widebodies, PSUs are now mounted so high it is impossible for most to reach it without standing up. And then the flow of air would likely affect everybody within a 1 seat radius...
I'll do my own airline. With Blackjack. And hookers. In fact, forget the airline.
Weight is the primary reason people pay me to engineer gasper system removals.
Although as a pax I prefer to have them, on some models such as the 747 they just move used air around and provide nothing fresh. On that model all the gaasper air comes from above the ceiling just aft of the upper deck. On 767 and 777 it is a mix of recirculated are and air from the main distribution system. On 737 and A330 it is the same air as the main distribution system.