Gabion Wall (they are everywhere in the Netherlands)

These are indeed not uncommon in the low countries for different uses, but most often they are filled with rocks or gravel rather than wood. I presume in this case is to provide a living space (and perhaps some food) for small creatures while keeping them somewhat safe from larger predators.

As far as gabions go, Snowleopard, you will see a lot of them when you visit Zie-Zoo (both filled and unfilled).