Amen. Dad brushed that shit off for many years. The last few years, after one of those customers (like in the video) showed up, he'd just say, "labor is $xxx, it will take as long as it takes, and I can't get to it until next week."
That cut down on most of them.
When will people learn that the best deal you will ever get is when you drop your car off, tell them to do what they gotta do, and there's no hurry?