Discharge Zones
Animals shake after stress. In "polite society", we tend not to. There are many benefits to not spilling our emotional discharge onto everyone we meet- it lets us interface much more cleanly & prevents a number of problems. It's good social hygiene.
In our effort to maintain good social hygiene, we tend to sweep our less-than-polite impulses under the rug.
Shaking is, except in a few circles, not encouraged. Many of our inborn regulating behaviors are prohibited by subtle cues and/or explicit chastising. This leads to all kinds of less-than-ideal coping mechanisms and restricts the "appropriate" spaces for emotional discharge to a shrinking number of realms.
Still, all of that emotional discharge needs to go somewhere. All the gunk that builds up in our systems that isn't metabolized needs to come out.
Raves are incredible spaces for emotional discharge. They create social affordances unavailable in many spheres of social interaction. Going apeshit is encouraged! Nudity, drugs, wild dancing, shouting, shaking! The no-holds-barred-porta-potty-nasty-molly-water-sharing-kiss of a rave is the necessary antithesis to clenched-asshole-type social hygiene.
The kinds of ecstatic, high energy emotional discharge experiences that occur at the edge of (or outside) legality and social acceptability are a load-bearing component of our society's waste-elimination infrastructure. Without these moral-panic-inducing events, we would be worse off. I might go so far as to say that if they happened regularly enough (assuming we don't integrate regular emotional discharge into our everyday lives), society would get much better.
The kind of temporary autonomous zone inherent in some raves is the equal and opposite reaction to stifling authentic emotional expression in everyday experience. Without them, unexpressed emotional discharge compresses and loops back in on itself to create trauma resonators that do more damage than the emotional discharge itself!
Raves can be discharge zones for emotional waste, but it's interesting that they tend to be particularly wholesome. The phenomenon of the "rave mom" might even suggest that raves are places where people can get previously unmet developmental needs met by surrogate parental figures via the transformative power of MDMA!!! (but let's not get ahead of ourselves.)
All that said, I don't think raves are the only/ideal way to handle emotional discharge, but they're certainly load-bearing in a way that other less intense kinds of social gatherings aren't. The intensity of that discharge is necessary and can't be properly handled in many other contexts. There are plenty of great ways to discharge emotions in healthier, more integrated ways, and raves come with their own slew of problems, but we don't have the waste infrastructure to take over the function raves perform. There's more gunk in the system than the sanctioned sanitation teams can handle. While we're laying the groundwork for those things, let's remember:
There's something sacred in the profane.