The system was created to encourage people to invest in the creation of new ideas and products. It's not always just an investment of time, which means you have to make it property that can be owned, traded and sold, with a known term. In your system where copyright dies with the author, the interests of others who might invest in a project or stand to gain from it (like a creator's children) are not looked after. By this mindset, everything Steve Jobs helped to create would now be free for "the public" to do with as they wish, and I imagine a lot of people would have stopped funding Steve's ideas when they found out he was sick.
> You could really turn your proposition the other way around: if someone doesn't want non-paying readers to read what they write, then they should refrain from writing anything.
I could, but it makes no sense to me to tell people who want to be compensated for making something valuable to stop doing it so that we can make whatever remaining works there are public domain.