Maybe they have a new rank system and that's worn by Jounins or Upper-Jounins, Kages, or the leadership of the village now.
I was going to suggest maybe it's a Fourth War Hero thing (like a medal of honor) but Sakura doesn't seem to have one. Remember how like while the war was going on, all the Daimyo were hanging out and passing the time by talking about the kinds of honors they might want to give out when it's over?
Or maybe Naruto personally gives them out as he appoints folks into different roles for that New Era Project of his.
Or it's an alliance thing. It's supposed to represent "friendship" since it originated with their alliance with Uzushiogakure. So perhaps it's more inclusive now, representing the expansion of their alliance with all of the ninja villages.