Anecdotally, I know of one child who was homeschooled recently. The mother is a single mother, of modest middle-class means. There was a homeschooling group nearby with a few volunteer mothers handling most of the logistics and teaching. This particular mother did not have to give up her job. It does stretch the definition of "homeschooling" a bit when it's a neighbor teaching in a neighbor's home, but they made it work.
Is this family well off financially? Of course they are. I suspect the data on homeschoolers is going to reflect a generally affluent slant.