Yeah. They get your number by placing bogus want ads. I hope you all get cancer in your [***] and rot to death.

They absolutly do not get your information that way.  The ONLY leads they call on are from banner ads, or other ads strictly showing interest in continuing your education, on some job search sites they do have a page that asks if you are interested and you can click yes, or no and more on to searching for jobs.  
Even if your number is on the do not call registery, if you request information you give people permission to contact you.  
If you want off the list, all you have to do is either answer or call back and saw you are not interested, you will be removed immediatly.  
They are a free service to assist people who showed interest, they do not want or sell anything.

All you have to do is answer if they call or call back and say you are not interested.  Easy as that, you are removed from their lists right then.

That is not true at all, all leads are legitimate and the call is a free service that helps you get additional information for schools that offer classes or degrees that you are interested in.

this is EXACTLY how they get your information.  they get it from craigslist, unfortuately i fell for this a while ago