They have a backwards invite system in place. One person has to make the online room and then the others have to search for friends room to join it.
I was starting the ninth hole of the bonus course one day when the lucky chance popped up. I finished the round, got rewarded for lucky chance and it was still open. I was able to burn through 2 more rounds taking shots really quickly and not caring for my score.
Right now I'm getting most of my gems trying to fill out my gallery. Though being able to jump from open course directly to open course now saves a ton of time. It's just still really boring.