As you have probably realized, you can paint badges. Well, actually you paing badge types. As other things in the game, this is just for fun, just to show the others your liked images and to increase excitement when picking up badges.
But, badge (type) ratings also feed into other parts of the game via delivering diamonds:
Note: Details have changed in September 2019.
As diamonds have many applications, to gain power in form of skills or badges, consider to deliver the community some nice images.
See also: Statistics: Most Exclusive Producers, Badge Parade, Badge Parade 100 days