Or it could just be a certain way of framing things?
But for the benefit of this debate I'll state my bias. Almost all my travel is as a group.
But in most other facets of life, we save by buying more, right? (buying wholesale, buying bulk, etc).
So I've actually had the other feeling... if I'm buying 4 tickets at once, can I get a bit of a volume discount? And I'm not sure that's what the airlines are doing here (I don't ascribe any altruism, it's probably more that families were getting cold feet with increasing prices), but I like that I get some kind of cheaper rate when I'm buying 4x of something, just like in just about every other purchase in life.