You're saying those photos are real? Don't 'insult my intelligence'. [=don't treat me as though I am stupid; don't expect me to believe those photos are real]
Most people were forced to work longer hours each week, and to 'add insult to injury', the company decided not to give pay raises.
They're understandably 'insulted' when no one asks for their opinion on a matter that affects them so much.
(..) Never has, never will. Oh, Frankie. Frankie, why do you keep on with the insults? - I would not insult you, Mr. Vivaldi. - When you lie, that is an insult. You are Jack Slater's favourite cousin. You talk all the time. I must know what Slater knows and you are going to tell me. (..)1993 Last Action Hero