Glue-lams are not used for walls, they are used for floor support. While a lot of multi-unit concrete residential construction in Germany uses concrete for the floor without supports), for single family houses there it is still relatively common to span rooms with beams to create floor support.

This is also true for earthen buildings, which are remarkably popular (on a per-capita basis) in Germany. I say this as a US resident in New Mexico, where it is hard to imagine a place (Germany) less likely to use variants on the same best-practices as housing we build here.