Two questions actually :-)

I know how to do it but i wondered whether the items in the shop/ gallery are safe. Do they just stay where there are, just loosing the pricing? Or are they deleted? Or put in the inventory?

And if i delete a shop/ gallery, are the items deleted or ware they put in the inventory? Is there a difference between shop and gallery?

They stay there. Instead of the price, there's 'Display Only'. And if you delete a shop/gallery, all the items inside will be deleted. The difference between those two is that Gallery items will have 'Display Only' and are thus unbuyable.

Thank you!