Earlier quoted context omitted.
You’re describing something different, which is just paying later. I was objecting to someone proposing reading books and then paying only if they thought it was good. That’s the part that isn’t commerce, because one side is making use of a good and isn’t compensating the other side.
I mean, I also didn't pay for stuff I tried and didn't think was good. (Which reminds me, one day I should actually buy the Warriors series of books since I only read them from a library once...) I throw money around a lot more now though, I tend to just buy something and try it and only ask for a refund if it's really useless (like was a macOS app called Vivid that ruined video playback; Lunar works much better). I…
Yes, interesting case. I'd say the difference is that those theatres are agreeing to those terms. With books, I think it's fair to read chapter or two in a bookshop and decide if you want more. But if you read the whole book, you can't then just say "That wasn't great, I won't pay". Nobody agreed to those terms, and you're getting the product of someone's labour and just declining to pay for it.