The reason I left one development job
A few years back at a place I worked:, the CEO said, "I never hire anyone over 40"
He looked at me with his early 30-something wisdom and reasoned. "They just don't get it."
"You just unhired me," I told him. "Well, you're different," He said. "I know it's not a good rule. But I still try and follow it."
The thing is, he's not that different from anyone else. He just has the insight to acknowledge that he was blowing smoke out of his ass.
We all make arbitrary rules that we follow, even ones we openly admit are based on fairy tales. In this specific case, his rule was just as arbitrary as any other. It was just also really stupid.
But developers do this kind of thing without giving it a second thought. How many of us are staunch advocates of camelCase or putting brackets on their own line? How many of us refuse to use one or another framework because "it's lame"? How many of us refactor because it "eliminates duplicate code", regardless of whether or not it makes the application less readable and maintainable?
It's human nature. We have to do it. It's how we get through the day. If we didn't we would have to come up with some semblance of a reason why we do the million little things we do. We would be so busy trying to rationalise why, that we would never end up doing it in the first place.