And how did Sisko get that location for his restaurant in the first place? What if someone else also wanted that location for a different business, did they wrestle in the street for it? Or did Sisko out bid (money) the other person for it? Housing (as in a house) apparently isn't. Kirk owned and later sold his house. Because Grandpa Sisko had a restaurant, and not just a large room with tables in his home, food is sold. Given that they are buying and selling property, mortgages likely still exist. The impression I've received from the show is that robots and robotics are not completely unknown, but are very rare, jobs are done by people. When Deanna was taking her bridge officer qualification test, there wasn't the option of sending a machine into a radioactive area to effect a repair, she had to send a person. Interesting idea, the more you put into society, the more you get back. Expend no effort, and you're be a protected, provided for second class citizen (maybe third class).