Quick anecdote: I was working at Intuit and redid the Quicken.com homepage. I added some icons and moved some stuff around. The marketers also changes of their own on their own version. Nothing goes live without extensive testing, so we all put our A/B tests into the hopper and waited.
My design won by alot, and made Quicken over $20,000 per month immediately. Then came the interesting part...
The marketer refused to promote the winning test to the site. She said, "I don't like the icons".
So what's the lesson? We live is a messy world with horrible people who are not interested in success or user happiness or even money. People are interested in their own egos. Personally, this is the worst part about knowing how to design. You know what will be successful, but we don't live in a meritocracy. We live in a bureaucracy.
I feel your pain deeply. One can not buy groceries on principle. You have to decide when to fight for what's right and when to smile and let the other person get what they want. Figure out what matters the most and everything else. Make sure other people decide "everything else" and you fight for what matters. I wish this answer wasn't so cynical. Hopefully, it was a little helpful for you to know you aren't alone.