The arrogance! This is one of my pet peeves at work: When someone looks at another person's work and judges its value or difficulty. "That's easy." "That's pointless."
Ugh.
Everyone else's job looks easy and/or pointless until you're the one doing it. Then it's important and challenging (hopefully).
Most people who feel their own work is pointless simply don't understand how their role fits into the bigger picture. I assure you, the profit motive is very good at weeding out truly unnecessary costs. It may lag, sometimes. But if there's a dollar being spent that doesn't need to be spent, someone is going to eventually find out and eliminate the expense.
I think this mentality comes from a deep need to feel superior to others. So when we can't understand or appreciate someone's job, it feels powerful to declare their work easy or pointless.
But that's just ignorance, arrogance, and, frankly, bullying by other means: I'll make myself feel bigger by making you feel small, and I'll do it in front of all of my friends so they can affirm how big and tough and awesome I am.