The difference between running your own tutoring business and volunteering for a hacker school is that N dollars go into the school's pocket, instead of yours. Why would society care about that difference?
I don't know much about bootcamps, but there's a lot of hand-wringing in the UK about people working for free ("unpaid internships") in newspapers, high arts, TV and politics. Because it ends up that you can't get into those industries without spending a year working for free, and the only people who can afford to spend a year working for free are people with rich parents, so newspapers, high art, tv and politics end up dominated by the rich.
Admittedly, in the SV programming climate this is not currently much of an issue.