Good point, I have mainly been printing these items for the hydroponic tower. I do have other versions that I can check. I think after this set prints I will add some basic shapes in different orientations to see if there is issues still.
That being said I did print some other items that were stacked and each one is much thinner but there are no artifacts on the outer walls.
https://hackaday.com/2022/09/05/food-safe-3d-printing-a-study/