Well, what if you don't have the tutor and mommy or daddy is doing it?
Given the right curriculum, parents can become as good at public school teachers. Out of all my years in school, the teachers have pretty much given us work from a book. That book tells you how to do the problems, gives examples, and quizzes you so that you learn the material. All the teachers really need to do is further help the students when they don't understand. Now, if a parent was given that same book, wouldn't the student be able to receive the same education?
And again, home schoolers can still interact socially if they decide to do so. There are hundreds of programs for just home schoolers such as sports, extracurricular activities and field trips. Not to mention all the after school activities that are also available to home school students.