I wonder why the organizers don’t ASK those people who didn’t show up. I think the picture would become much clearer.

For me the main reason not to go was the size of the event. I bought a ticket rather early but after giving it some thought I decided that don’t feel comfortable among a crowd of thousands.
As a self employed freelancer who doesn’t get a refund from her boss costs are an issue, too. I have to choose carefully where I spend my travel money – I think I will go for the smaller camps in the future. There are plenty on very lovely spots ?