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.
(..) the Tooth Fairy. The Tooth Fairy's been visiting Michael Vincent almost every week lately. Well, aren't you concerned it insults his intelligence? Michael Vincent is six. Which means he is old enough to understand you are essentially perpetrating a fraud. (..)2015 TvShow: Bones Title: The Promise in the Palace Season: 11 Episode 7