Phew!A fair question.
In German I'm an Arbeitserzieher, which is a cross between a social worker and an occupational therapist in the UK. Germany has networks of workshops for people with disabilities, and I work in one for people with Psychological disabilities as a sort of supervisor, and one of my departments is a wood workshop. Hence the need for work boots.
I thought you wore them so when taking kids from their parents you could ' stick the boot in'.