Geez a permit to put in a door? I know of a house built within the last 2 years that didn't have a single permit. Nobody really cares.
If you want the door, just put in the door.
You must not be very smart, or just happen to live in every neighborhood in the country or even world to know that nobody cares, or did you just not clarify you are only talking about your area when you said no one cares? Blanket statements are dumb if that was one. Sorry, but one of my pet peeves is people who assume things that can vary wildly and those who miss the important detail in what they state or read.
25+ years ago, my city wanted a permit just to install a mercury vapor light over a residential driveway.
There are certainly regulations and people who do care in plenty of areas. You may be lucky enough to live where no one cares. What is required and what you can get away with can be different things.
A person only needs to be able to crawl in or out of the garage for a door failure. A utility door mounted low and between the studs would be easier and less visible while serving the purpose and it can be more of a DIY job.
A man door makes sense and can vary in installation difficult depending on the structure, but there are many pros out there like me and even others who could saw cut a thick concrete wall if it happened to be that extreme. A straight forward install could be done in a day, but sometimes issues arise, especially with old work. Location of course matters, especially if Murphy rode in the back seat and decides to mess things up.