This feature may appear useless but it can give leader's a quick insight of the theme composition of his whole theme with a few swipes. This information in the right hands can be useful, but besides that it can make the list look a bit more colorful (come on Toller humor me : p). If a leader would want to find out about this information he would have to click on many members, action that takes a while (specially in slower phones that need longer loading times).

This feature can also be good in combination with the ability of viewing your team members' levels. If a leader/co-leader would want to view someone carrying the team deck; she/he wouldn't misclick on people who don't have the choices for that week, (because of the different theme logos).

This is a minimal change but it can help some people and it may be easy to implement for the new UI developer. My suggestion would be to place it to the left of the donation amount and to the right of the member's rank (member-elder-co-leader,leader).