WC event buffs still on star menu

If we can use for nothing the buffs we've created for the world cup event, why they are still in the star menu and showing in grey color?
We cant recycle them, we cant put in in trash bin or something, but they are still there. Is really boring watch at them every time.

They were made deletable after the last maintenance, should be a red x to click i think (didn't have any buffs left over myself, but have heard of others being able to delete their buffs).

I want to slide tackle a Witch Tower.. =(