I played ballrace once and I joined an already made lobby that was about a round or two in.
When I joined, they got super aggressive and kept telling me to leave.
Of course I just ignored them, because they made a public lobby.
They ended up closing the connection before we even got to finish the game
I didn't care that much, but it just annoyed me that they got mad at me for joining their public game. There's a friends only option for a reason..... (maybe that doesn't work or something, idk)