I was under the impression there was overwhelming effort put into environmental maintenance on-site - ensuring that as much as possible, all traces of the yearly occupation are eliminated after the end of the event.
- travel to and from
- consumables and their transport
- air conditioning onsite
- burning things
If you start segmenting the set of people along all possible dimensions in order to find "local outliers", then eventually, everyone will become an outlier in one of the sets.
I think it's reasonable to say that everyone should do as well as they can, and if everyone does that, the average person will have an impact.