Yesterday I was playing with a friend from our game club. We formed a close group and started a patrol quest. However, whenever we entered a system, there were other players autojoined to our group. Will this be happening all over the game? Won't I be able to fly around just with 1 or 2 of my buddies and always have random strangers with us? For example, we had one occurance where such a stranger first grabbed all the anomalies in the system and only joined in the infight in the end for a bit. That means we did all the work and he finished the quest nontheless.
I wouldn't mind if I enter a system solo, but when I'm already in a group, why can others join? Especially when I form a closed group?