A lot of employers want people they can understand and they can trust.
The companies I work for generally don't want someone that's creative. They want someone that's dull and reliable. Show your creative side and they'll look for someone else, even if you've got 10x more skills than someone else.
Given that creativity doesn't pay anyway (there's a cap on pay and I've already reached that cap), there's no point to show it. I can get hired based on what's on my resume alone and by answering the same set of questions they always ask.
Then I get hired, I automate everything in under 6 months and I go sit on my ass or do something else. Flaw in the capitalistic system. I know what I'm worth, I can bring across what I'm worth, but it's simply outside the bounds of what's expected or needed.
And I know that sounds weird, but think of it like this:
No one is going to pay the fastest cashier in the world 3x minimum wage. Not even if they check out customers 6x faster than the next person. And claiming you're the fastest cashier in the world during the hiring process just gets you thrown on the discard pile.
The same goes for a lot of other professions, including mine.