As long as there has been knitting there have been battles about it. There are self-declared "yarn snobs," who frown on using anything but natural fibers; "gauge snobs", who wouldn't be caught dead with chunky yarn; and "experience snobs", who claim you can't declare yourself a real knitter until you abandon novelty yarns. The truth is that the knitting world is a tiny metaphor for the real world. It takes all kinds.
I will not allow myself to feel bad if someone disapproves of my knitting. I will also resist the urge to stuff his mailbox full of chunky acrylic fun fur at 3:00 am.