I stumbled on a free collection of short stories by Mack Reynolds, the mercenary-turned-science-fiction-writer! He focused on the economic and sociological aspects of the future, writing often about (for example) a universal guaranteed income back in the 60s and 70s!
The ebook is free, well-formatted, and available in all the major ebook formats.
https://standardebooks.org/ebooks/mack-reynolds/short-fiction
And then I checked Project Gutenberg. A HUGE number of Mack Reynolds' books and stories are in the public domain! I should note that some of them include a bit of softcore pornography, although I haven't checked the specific books on PG.
"Black Man's Burden" was particularly notable, as I recall - not as porn (don't remember if it had any), but in it's approach to race. Anyone familiar with the famous poem by Rudyard Kipling will, of course, recognize the source of the title.
Here's a link to all 33 of his works on Project Gutenberg:
https://www.gutenberg.org/ebooks/search/?query=Mack+Reynolds
Quasit