Deffs not the first person to have this idea but itch.io shirts n merch would be awesome!
Like a t-shirt or a bag with the itch logo or even the li' 404 error skeleton character would be cool.
Even  a super cool idea might even be like chuck the idea out to the community n do a comp or commission type thing for the designs.
EIther way, keen to support the platform beyond just including a cut of game sales and this might be a cool idea.
:3

I, for one, would like this idea as another way of supporting the Itch.io staff. I'm not sure how they are funded but some swag would be hot AF!
Running their own merch site store would create more work for them even with their merch provider doing all the real production.
But it'd be worth it in the long run