I agree. I also ponder on this.
But I know that our reaction to prices and goods is much more emotional than rational. I'm mostly describing how I'm feeling.
The conversation of value is interesting. Creators will talk about what it cost to create the product, or what it would take for it to generate profits and pay employees a certain amount. On the side of customers, there's a ton of factors: your level of wealth, how genuine your interest is, personal preferences, how much you bought recently, etc.
I hate reading through books in PDF form. I only use PDF as reference on my laptop for quick searches. Through this preference, PDF have inherently less value in my eyes than the physical product I fawn over. It's also difficult for me to associate value to something that's entirely digital. Buying a Bluray for 15$ means owning the movie, buying it for 15$ on Amazon Prime feels... different.