AI Matchmaking and bug

I am unsure if it is a bug, but if it is not it is poor design. I am new to the game playing AI just to get to know the game. If I can’t get a match with a full 5 human players I get 1-2 human players and a couple of bots (fine)…

But when the above occurs and human players leave im forced to play alone with bots… I cannot even leave the game and it will simply put me back into the game. I cannot just afk the game or else it exits me from the game… Can you please advise me is this an intentional feature of the game or a bug ?