"That being said, the very nature of the event involves spending thousands of dollars to live in the desert for a week. So the audience is obviously mostly people who have the money to do so."
It depends what standard you need, but I have been to (way smaller) desert gatherings where people with no money came. (Not as remote, though, possible to walk there with a tent). But as far as I know, the main thing you need for burning man is a van and water, or know someone who has one.
You dont need a van. You just need to be comfortable at being uncomfortable.
Yes, tickets are expensive. Yes you need to bring survival stuff like water and food. Yes you will be underslept most likely. But it will be worth it.
> the main thing you need for burning man is a van and water
And $1000 tickets :P
A fully equipped van is also not exactly a cheap thing to own or rent.