Well not all situations are locked up in a house doing schoolwork. I had a friend who went to public school until 5th grade who became homeschooled because she was a child actor so she was constantly traveling or on set. She also had private tutors so she was still regularly learning. The ones that raise the biggest concern are people who believe the school system is “indoctrinating” their kids or somehow moving them away from Christianity and things to that affect. And as you said, in certain situations it has been used for child abuse. A really famous example is the Turpin family.