SE stop restricting this game out of fear.
What people are missing due to fear of "This guy is going to get something I want that I deserve more, please don't let people help him." is what will restrict this game to a point where people will get bored so fast they will probably quit because they can't even help friends out with the content that matters.
Fear of groups selling is a poor excuse to restrict a much better way to deal with helping out your friends. And sure people are going to say "Well, after a few weeks no one will want to help eventually and get bored." This is one opinion, but it really is void when the relationships between groups of friends is different with each person, not everyone is going to act like that, lol.
People have FCs with leaders that actually build groups and can't participate after a group is made or if the group is short and now I feel like I'm just repeating the same thing over and over which I am.
The point is made, the positives out-weigh the negative, it's clear what people want and they see the what they could achieve if you made this possible.