Why are Custom Games Ignored?

The custom game feature has been around for ages but Riot never seemed to tap into the extreme potential these custom matches offer. The community used custom games to create creative new ways to play such as ARAM(which actually spawned into a game mode) and Hide and Seek. Imagine if custom games had specific off/on options when creating a mode such as but not limited to; infinite gold, restricted items, friendly fire, life system(where if you die x number of times you lose the game), and obviously these can be subject to change. Imagine the possibilities of cool different game modes that the community can create. Custom games should be, in the name, customizable. I know Riot may be scared of too many people joining custom games and leaving the queue pool because there's no way this notion hasn't come across their minds however, I can't really find any other negative with this besides a bit of resources. What are your thoughts on enhanced customization of custom games?