They scorned the word of God, found it boring and tedious. Jeremiah appointed out that their biggest sins were that they were greedy, from the richest of them to the poorest. But the most telling statement about this group of people was that they ere not ashamed. They were not able to blush. In the east and in the near east shame plays an important role in society.
Societies are very tight knit.
They rely on each other to survive daily, especially back in Jeremiah's time. So when an individual acted badly, in a way that harmed the community, the community had a powerful sanction it placed upon that individual- shame. Shame was felt by the offender and the offender's entire community. It was a horrible feeling that came from knowing that you left everybody down. Shame sticks to a person.