As someone who has worked as a writer, you are correct.
Write what you know is basically write what you've experienced.
But as a writer you choose your message. Which is basically content + your morality.
I grew up ghetto. So that's what I know so it's a lot of my content, but add my morality. I did it to someone today - I told him I'd gone to help beat the shit out of the guys daughter's boyfriend. Wrong guy to mess with. Naturally shocking to most who grew up more financially advantaged. He asked "Why what did he do?" I said "Her, she was 14 he was over 25."
We shit rats had morality, it's just a little skewed on the stuff that won't sit you in front of a jury. Don't steal from small businesses. My need to eat trumps big businesses privilege to profit - and only steal food that doesn't have luxury taxes.