https://www.shutterstock.com/license
From what I understand from here it requires an enhanced image license.
It certainly looks like an Enhanced license is required but see the retail price of the T Shirts - $10 or $12 or so. That certainly doesn't allow for paying for the license and the production costs of the T shirts themselves yet alone a profit margin. Perhaps someone who has their designs being used should contact Shutterstock for clarification. Regards, David.
Thanks both for ideas. I don't see any of mine, so someone who does nice vectors and real illustrations might ask for us?
I'm not trying to pick on this shop or cause them any trouble, I just wonder what license for on demand T-Shirts. And yes, it can't be much, if they can sell the shirts at the prices they do, get a license and ship. Not much room for profit. They do list Shutterstock and the image and the artist, which is up front and unlike so many others who try to slide under the radar.