Yup, this raise one of my big complaints about some SciFi stories: lack of economic plausibility.
Science Fiction is great for looking at how we might deal with various potential technologies. Readers are perfectly happy to suspend disbelief and accept whatever technology is proposed. What readers aren't willing to do is suspend disbelief and accept people behaving implausibly.
To write good science fiction, you need to accurately portray people. You can make up the technology, but you have to get humanity right. And that means you have to get the economics right.
This is exactly the problem I had with reading the Hunger Games. Everything worked, except why would a society with hover cars and other advanced technology have need of the services of the districts? Surely they didn't need coal, and yet they had a whole district dedicated to mining it. The lack of economic sense pulled me out of the book. Instead of thinking about the characters, I was thinking about why the society that was described didn't make any sense.