How do I delete or get control of empty 'invite only' clubs?

Maybe refreshing the gameplay folder will clear it:

1. Exit the game. Move (not copy) Saves, Tray, Mods, Screenshots, and Custom Music folders and the Options.ini file to your desktop. If there is a folder inside Saves called Scratch, delete it.
2. Delete the rest of the The Sims 4 folder from your Documents > Electronic Arts folder.
3. Start the game, and exit the game. Now you have a fresh Documents > Electronic Arts > The Sims 4 folder.
4. Copy all the folders and the file back and start the game again.