As an example, Minecraft is only a $20 one-time purchase, but free and/or open source mods made by people who are motivated by fun instead of profit have created a staggering amount of content that happens to be really addictive to someone like me. For the $20 I got the equivalent of years of content and novelty that I can never hope to fully explore.
I wonder if any given computer program that's given a colossal amount of development resources thrown behind it will ultimately come somewhere close to irresistible, and would suck away various parts of our less interesting hopes and dreams regardless of how much monetary currency the creator is expecting the user to pay. There just happens to be a motive to tack on some extra profit if the game is pseudo-irresistable, where all that time would have been "wasted" on someone's freeloading video game addiction instead. It makes me wonder if what is known as "predatory" is just a pathological explosion of what someone thinks of as a successful accomplishment (my "any given side project could one day addict us all" theory).