I'd substitute the word "entitlement" with "expectation". And it's not hard to see why they'd have it. I'm 29, and I can clearly remember getting the message from every corner of society that more education = higher income/earning potential. From every teacher, guidance counselor, and regular adult in my life the message was the same. College education means financial security.
That entitlement is a huge question. Why should they be entitled to higher paying jobs? Because they worked hard to get there? I used to work 12 hour days as a construction worker making $10/hour. I work half as hard as a programmer as I did as a construction worker, yet I earn 8 times as much. In the 4 years of school it took to get here, I can't even pretend that I worked harder than my former colleagues did. Clearly how hard we work isn't the only factor in our wages.
So what is this entitlement based on? I'm not asking what wages should be based on. We almost all agree that you should be paid according to the value you add. My question is why it is (or why is it supposed to be) surprising that someone with a PhD in medieval studies can't find work. What is the assumption by the general public based on?