How do I get random people to join my Custom Game? (And more questions about how custom games work)

I created a 4v4 ABAM (All Blind-Pick All Mid) Custom Game and waited for 5 minutes a couple times, but no one ever joined it. When you create a Custom Game, is your game automatically added to the "Join a Custom Game" lobby? If so, are all the games listed there literally all the active Custom Games on your current server? Because of the thousands and thousands of players, there's only like 30 custom games (or less?) shown on the list at a given time.

Do people not play Custom Games with strangers like at all? If they do, is there a protocol I need to follow to let randos know they're allowed to join? Like include (Anyone!) or (OPEN!) in the title?