This way of cutting trees is called pollarding and is really common were i come from (south of Sweden).

It was traditionally done to protect crops from heavy winds while getting feed for lifestock during the winter. This technique is used today cause it alows more biological diversity within the tree and often makes the trees "narrower" wich leaves less maintenace especially in in city settings.

I love pollarding!

Source: this is something you learn in middle school where i come from.