The key difference between a team member and a supporter
Team members: People that will directly benefit from the funds raised - they can track how much money has been contributed to them (I.e., for a sports team, that would be all the players, coaches, and parents).
You can invite team members by clicking on the Invite team members button on the Members tab as seen below:
Supporters: Individuals who donate or shop by contributing their earnings from their purchases to your team. I.e., this would be fans, friends, colleagues, and extended family.
You can share your team with supporters by clicking the Share icon at the top right corner of the page as seen below: