So you've got a very strong opinion on this matter, enough to post it publicly, and you've never heard of Christian curriculum?
Never heard of Apologia Science ("Apologia provides fun and challenging K-12 creation-based science curriculum...")?
Never heard of incredibly popular "Student of the Word" bible-based curriculum that bases all subjects (math, geography, history, science) on scripture?
Never actually typed "bible-based curriculum" into google and seen the quarter million hits?
And yet you still feel confident enough in your knowledge of the topic to publicly say "homeschoolers rarely follow a curriculum"? Wow.
Do they follow the normal government approved curriculum? No, some don't. Do they follow a curriculum? Definitely.
(There's a tiny (less than 10) percentage of people who identify as "un-schoolers" who don't actually use curriculum as a matter of philosophy, but the true unschooler philosophy is to guide your children to learn on their own, and most are quite serious about it.)
Of course I see a problem with people who do what you said to their kids. But that's not most homeschoolers. That's not even a barely significant percentage of homeschoolers.
There are people who abuse their kids who go to school too. Be mad at child abusers, not homeschoolers.
Sounds like you have a personal axe to grind with your parents and you're transferring it on to the homeschool movement as a whole.
You are sadly under-informed and your opinions are based on your personal experience and not the real statistics or experience of the actual national homeschool community.