I seem to remember Feast (rarely) doing this. If someone left or d/c 'ed before a match began, the system would call a draw or somehow kick players right back out.

Why that got removed I have no idea.

It's not like it would be exploited since the one who leaves has to wait 30 minutes before they can queue again.

No one loses stars, the match doesn't even start. Just a draw and back out you go.