Farming minions in this game mode doesn't seem as important as getting kills, because the kills give so much and the re-spawn timer is wayyy low. So, opting to lane and stay flexible is better than having a wandering jungler. Lane phase is kind of just about kills and securing and contesting the alters for the 160 gold-- contesting the alters takes the entire team, a jungler can't do it by themselves.

Games are going 30 minutes on average because it's just so hard to push an inhibitor when the other team just keeps coming back for more. Whats to risk when you can just respawn before they can win the game anyway.