2020 update: the eggs actually became available in supermarkets (REWE) for little extra cost, but are subject to regional availability.
REWE is a little bit away from my location.
Edit: the article is from 2018. Lidl has announced recently that they plan to have that for their organic eggs starting in early 2021 and their free range eggs until end of 2021. Source: https://unternehmen.lidl.de/pressreleases/2020/200714_lidl_e...
This is great! Hopefully Lidl will have them in other countries as well so I can buy them.