"Attendees"!
Someone who attends an event is an attender.
Someone who is 'attended to' is an attendee.
So at a gig the audience are the attenders, and the artists are the attendees.
The "..er" suffix is active. The "...ee" suffix is passive.
A referee is someone who is referred to. A referrer is someone who refers.
I saw a notice on a bus recently. It said "Seating capacity 56. Standees 12"
Standees must be people who have been stood up. How sad for them!
Cheers
Dave