According to the folks at complaintchoir.org,

In the Finnish vocabulary there is an expression “Valituskuoro”. It means “Complaints Choir” and it is used to describe situations where a lot of people are complaining simultaneously. [Talervo] Kalleinen and [Oliver] Kochta-Kalleinen thought: “Wouldn’t it be fantastic to take this expression literally and organise a real Complaints Choir!”

Thanks to their work, there have been complaint choirs around the world. Here’s an example from Chicago:

In a serious mode, I would complain about these complaints–where are the solutions? But I’m happy to lighten up and enjoy the show, in particular the natural juxtaposition of the merely personal with the grandly political: “Our president is a cowboy / I hate my homeowners association.” It’s the lifeworld and the public sphere all mashed together and set to music. A democratic art.