> Who's attending these? Is it mainly the old timers or are they attracting a strong following from new generations?

Mostly 20somethings as far as I have seen; invites are word of mouth (aka Whatsapp) and we stumble on them because we hike around a lot and then have a chat. This is during the day when the partygoers are chilling out usually.

Oldtimers are mostly dancing in local bars to small cover bands. Also until the early morning usually and no coke/speed, but just beer/spirits.