A restaurant can do just fine by making you a good meal every week, knowing you'll come back and pay them for each meal.
An engineer with an app can come to work 365 days a year, fix bugs, add nice new features, unbreak the app every time iOS updates, and, though you use the app every day, they can't count on you to give them another $5 every year - or ever again - unless you enter into a subscription.
This isn't to say you have some obligation to do a subscription to any app you don't think is worth it, but for apps from non-scam developers, they're usually like $20 or less a year - about a nickel a day. A nickel is 3¢ in year-2000 dollars btw.
It's on the developer to prove to you that the app is worth paying a nickel a day to have! But ruling it out just because we wish it didn't have to be, well, that just rewards the developers who monetize exclusively with ads or sell their 'free' apps to sketchy operators.
I'd like it if Uber was free or just cost a buck a ride flat rate, but I know that anyone willing to give me a ride on terms like that is probably looking to rob me.
A restaurant has to cook a whole new meal for every customer. An app developer does not.
We seem to be arguing at cross purposes. I am not saying that software is not worth paying for. $20 seems a very reasonable price for an application if it meets a customer's needs, and the only expectation I have beyond that is that it continues to work across OS updates. I'm OK with big version upgrades being a separate sale.
It's not the amount of the payment. It's the subscription model I can't stand. You're correct that I might use an app I like every day. But the marginal cost to the developer of me using it every day is $0. Rather than belabor the restaurant example , consider a book or a music CD. Writing books or recording music is generally a slow and difficult process, it takes months to produce one that might be read in a weekend. But if you buy a book, you can read or refer to it every day without paying again, or you cna listen to your favorite songs as often as you like by playing the CD. Nowadays many people prefer to stream music, but I think when people buy a book (even an e-book), they consider that it's their copy to read as often as they want...
...or not. If I buy a book and I don't like it, or later I find another book that I turn out to prefer to the first one, I can just not read it again. I don't have to cancel a subscription for the book.
Who expects 'nice new features' from an app they already decided to buy? Keeping the app compatible with new OS releases is necessary to keep sales going.
After a year, I don't think anyone is bothered if an app becomes unsupported for whatever reason. Usually what happens is the opposite - developer unnecessarily cripples an existing, perfectly working app, to try to milk some more revenue out of it.
This is an especially moot point now that most platform API upgrades are $1 of LLM work away.