Banking is unfortunately what makes hub and spoke work economically. I used to think the same things about banking relative to resource utilization (and still do to an extent) but one of my favorite books, Thomas Petzinger's "Hard landing: The epic contest for power and profits that plunged the airlines into chaos" (1996) addresses this: for every flight added to a bank the cost is incremental but the network benefits (particularly in terms of connection opportunities) are exponential. And most people are trying to get from A to B more or less as quickly as possible; relatively few are going specifically for hang out in a club or PL.

And yes, PLs can sometimes be crowded but I don't know that it is fair to say you can't just it -- has anyone ever been turned away from a PL?