Your pricing model is broken and it's bad for you and customers. Do yourself a favor and put a limit on support after the upgrade and then offer an ongoing maintenance package.
I used to have a similarly bad attitude when I had low metered pricing. Once I insisted on monthly account minimums I could afford to hire a nice customer service person and not be so touchy all of the time.
This is literally one instance in ten years. That's pretty far from "all the time", which is a conclusion I don't even hint at anywhere. I'm pretty happy to provide the service at this price point, and every customer is too. Besides, I would call out this kind of entitled rudeness at any price point.
I quite often throw out the “raise your prices” viewpoint in casual conversation, based on my time (12ish years) as a contractor. When I do it, I’m aware it’s not always the best option, but I don’t have a catalog of personal experience to draw on for more nuanced advice.
My example is not completely applicable because it's not a business per se, nor do I want to make it one, it's more of a "I made this for myself but you can use it if you chip in to pay for costs". Even so, I recently raised the price from $20/ever (where it was since 2008) to $50/ever.
The way I handle most support requests is to make the UI easy enough so that people don't have that problem in the first place, though many still do, partly because of the unorthodox "email token to log in" system I switched to recently. Many people weren't used to that.
That only works as long as your addressable market is growing. You see it on app stores. Many early Indy developers were making money selling 0.99 apps where you paid once and got free upgrades forever. That was fine when the iOS market was doubling every year. Now, lack of upgrade pricing is forcing app makers to either make money from ads or subscription pricing.
Back in the day Angry Birds cost $0.99 with no ads and you could use it forever. I downloaded it again recently just for nostalgia purposes and there is no option to get rid of ads. EA had a version of Tetris that cost $0.99 that was released during the 3.5” era was never upgraded, but stayed in the App Store until iOS didn’t support 32 bit apps. They replaced it with an ad supported version.
What is wrong with not continuing to make money on something?
Let’s say you spend $100,000 to make a piece of software, you sell it to 150,000 people at a $1 a piece... and that’s it. People don’t keep paying for it, but you also don’t keep investing in it. You move on to making something new.
I don’t like this idea that you need to keep making money off something that you made years ago.
It would be fine to move on but in the case of Angry Birds. Wouldn’t the company get a bad reputation if they didn’t keep the game compatible between the 3-1/2 inch iPhone up to 5 and the iPhone 5? When a new version of iOS caused it to crash?
But more importantly, if you bought MS Office for a one time fee of $100 and the next month, Apple introduced a new form factor or new features and either MS didn’t support it all or forced you to pay the full retail price, would you be upset?
People buy apps and expect them to continue working when they upgrade their phone. What are you left with besides ads and subscriptions without upgrade pricing?
Yes, very true. That's the incentive for me, a hobbyist with very few customers, but when you've captured a lot of the market and your users never need to replace your product with a new one because it broke, you'll soon hit a wall.
Certainly one time pricing with unlimited upgrades/support misaligns the incentives of the developer and the customer. That said, it's probably fine for a relatively low-priced product that doesn't have any particular lock-in--like a utility of some sort. Or a game. I sold a shareware program like that for quite a while and never had a problem with that model.
Clearly, there are other types of software that this doesn't make as much sense for.
I used to have a similarly bad attitude when I had low metered pricing. Once I insisted on monthly account minimums I could afford to hire a nice customer service person and not be so touchy all of the time.