I suspect that, in retailing, it's one of these things where 95% of the customers are fine, but that last 5% take up a disproportionate amount of your time and mental energy, whether because they're clueless or morons or whatever. That's how I think jaded teachers / professors develop: most of their students are okay, but that small percentage of "story" students create all kinds of artificial barriers and special exceptions and so on that make the teacher / professor not real pleasant.
The same is true of video game retailing. The 20 minutes I spent arguing with someone who'd bought a game, torn open the CD sleeve with the serial on it (THROUGH the serial), spilt coffee on another CD sleeve, and then demanded that I let him return it because it didn't support LAN play is time I will never get back. And that was hardly one of the worst customers.
We call it "understanding the customer mindset" and is something that every small business owner in retail does intuitively. When formalized, organized and budgeted it is called marketing.
The difference is that small business owners in retail usually have better social skills than software developers and, therefore, are way more accepting of people's flaws.
Based on what they say when customers aren't around, I'm not sure it's accepting people's flaws so much as just being careful to rant about them out of earshot.
> IT: "No, we probably can't run [important software] off your office computer and save money."
'Yes, I know we can get an HP desktop from Staples for $350, and yes, I still think that $10,000 is a reasonable price for the master database server.'