One More Sign of Substitute Apocalypse

So I'm reading a Slate article about robocalling-- why it's getting worse, why the FCC is only sort of helping-- when I come across this chart:

See #7? The seventh biggest robocaller in the USA is a robot looking for substitute teachers.

More than loan scams. More than AT&T. More than Citibank or Chase Bank. More, I guess, than my friend from card services who assures me that nothing is wrong with my account however-- well, I never get past "however."

Can anybody take a phys ed class today?

That's how bad the substitute crisis has become-- robocalling is somehow seen as a solution. Lots and lots of robocalling. Since my own area doesn't use any such system (we still post absences on a web-based service where substitutes can pick the ones the want to sign up for, like a kind of classroom Match.com) I have to assume some places use it very aggressively. I wonder-- in states where any warm body can be employed in a classroom, do they just cold robocall every person with a phone? Could such approaches be augmented with, say, one of those sign-twirling guys parked out in front of a school ("We'll pay you $100 to teach Algebra today!!!")

When I worked in the call center biz, one of the ways my bosses made money was to sell the contact info of customers, and as a blogger I'm actually offered lists of contact information for, say, left-handed iguana owners in Idaho. I wonder if the sub hunters are trying that ("We need a biology sub today-- have the robots call everyone on that Field and Stream subscribers list").

Contractors find day laborers waiting in the parking lot of stores like Home Depot. Could school districts go looking for substitute teachers in the parking lots of local Barnes & Nobles? I mean, if we've descended to robocalling, what could be any worse?

P.S. One other offensive caller that is a source of numerous complaints-- Navient, the student loan company.that has a record of being mighty aggressive in looking to get paid back.