If team members who were added to the agency plan as invitees require their own licenses, what's the point of having an agency account besides the increased sending limit per month?

Agency plan should allow team members to have the same customizations available as a part of the agency plan.
It's a little misleading and confusing that as an invited team member I don't have access to the agency's licensed features like customizing the email before sending to recipient.
What was the team feature intended to solve or do?