Ask HN: Do companies ever request test solutions to build solution benchmarks?

After an initial 1-hour telephone interview, I was recently asked to solve a 2-hour data analysis code test. It went very well, but shortly after submitting my solution, an HR representative had a phone call with me that focused exclusively on side issues, such as what were my preferences regarding open offices or how I work in teams.

I was not asked about any of these topics in the first interview, and only a few hours after the first interview I had received an excited email inviting me to take the code test.

At the end of the second phone conversation, less than 24 hours after submitting my solution, the HR rep suggested that it was probably not best to continue the interview process since my feelings about certain things did not match the company's current policies.

I don't necessarily disagree with that decision, but here is the unusual part:

Just hours after this happened, I saw a new job listing from the same company for a position with nearly the same job description. But the title had been altered slightly to say it was a temporary position with the possibility for permanent hire. The revised ad also made it sound like the position was far more junior than when I initially interviewed.

I'm reasonably highly ranked on Stack Overflow for the main tech used in the test. Is it possible the company just wanted to see what my performance would be as a benchmark for a baseline? If companies do this, what steps should a candidate take to avoid completing such tests and investing personal time that results only in giving the company free performance data?