Why is the featured product image not in the product gallery? Other themes and Woocommerce itself always does this by default.

Why is it that your theme doesn't?

See screencast:
share.viewedit.com/3PF64PXRV2rcSAqCiur8zP

Dear sir,
Because main image and Gallery image are different, when you add images in gallery image, they are prioritized, when gallery image is empty, it will show image in main image.
We changed another js for this layout, so it can not show both main image and gallery image.
If you want both of them you can submit custom work our developer will customize it for you.

Thanks.

It is default method for Woocommerce to have featured image show on product page. Poor that to have it in this theme we need custom work done.

You are right John! This is a default option from Woocommerce and should be present in this theme.

Dear sir,
As you can see in our demo, we changed other js in product page and they work differently with the default. It can not add feature image.
You need change other js code and style for this issue.
We requested to change other js in next version, you can wait to update or submit custom work to be changed it now.

Thanks