So basically students enroll in a scam college to trick people into thinking they are well educated, and then complain when the scam is revealed.

I don't think so. There are colleges (mostly online and often postgraduate only) where the 'student' is in on the scam. They mostly serve markets where promotion or pay prospects are tied to box ticking possession of a masters or PhD with no real consideration of the academic rank of the programs. Those really are about trying to trick people into thinking they are well educated - although you could argue that if no-one cares about the quality of the 'degrees' they're not really scamming anyone.

What Corinthian was doing was charging large sums of money to students for nearly worthless, marginally accredited or unaccredited education while telling them that they were receiving valuable, career enhancing education and recognised credentials. They were the marks and not in on the con.

Of course I absolutely agree that people need to take responsibility for their actions but we need to consider the context and determine what is a reasonable amount of due diligence to undertake.

First of all, our society relentlessly pounds the message into people's heads that they need to go to college to succeed in life. Think of how often an 18 year old will have been told of the importance of going to college by teachers, counsellors, and other authority figures in their lives (all of whom have themselves been to college). How often their parents (who usually will not have been) will tell them that this is what they need to do to succeed. How often the media portrays going to college as the right thing to do. In every sitcom set in a high school or with high school aged main characters, applying to and getting into college is eventually a major plot point.

Now compare that with how often those same sources mention the difference between applying to a community college, a state college, a private non-profit, and a private for-profit college. If they even know the difference (which parents who haven't been will almost certainly not).

Think about the government services which poor people tend to interact with, and the American attitude towards public provision and realise that the educational superiority of publicly owned community colleges over privately owned colleges is actually anomalous. (and in fact the most prestigious American colleges are private, just a different kind of private). How on Earth is a teenager supposed to figure that out.

Should we expect an 18 year old to understand that regional accreditation is better than national accreditation? I mean, does that actually even make sense?

So while I agree that there is a case for people taking responsibility for their actions, I think that young people doing what society told them to do and making some poor decisions after being lied to have met the test for contextually reasonable due diligence.