Mickocado Avocado

There is a downvote counter.

Then how come is does not show?

It pretty much shows if you go over to your images tab, all submitted images will then show it.

You can also see the counter if you are a Stream Moderator when a post is flagged.

"It pretty much shows if you go over to your images tab, all submitted images will then show it."
That does not show the downvotes for me

I agree, they should be added.
Although there is a way to see them for images in streams you moderate.