I think your argument misses the point because any able bodied person can attend Burning Man if they make doing so a priority in their life. No one is arguing that people who don't care too much about attending don't manage to go, and frankly, even with a bunch of disposable income if your trip to Burning Man was "easy" you're doing it wrong.
I don't know how I can put it more simply: it's definitely not true that any able bodied person can attend Burning Man.
I guess we'll have to agree to disagree then because I've been a dozen times and I've met both able bodied and disabled people there from literally every walk of life, including self-described homeless, octogenarians on fixed incomes, people suffocating under medical bills for their cancer treatments, and folks from a dizzying array of far away countries.
I'm arguing against the idea that "any able-bodied person" can attend Burning Man, or events like it. Lots of healthy people cannot afford to attend events like that, for multiple reasons.