Or it means that among the hobbies you have that consume your free time, there is 'tech' as a line item. There's nothing wrong about doing research in tech in one's free time if that what they enjoy doing.
It's really annoying to read replies like yours that systematically suggest all people who spend time researching and side-projecting stuff about tech are doing so because they have lot of free time or are cannon fodder. If you prefer to spend your free time gardening or brewing beer, that's fine. It's equally fine if I enjoy spending my own time learning about more tech stuff.
I didn't mean to suggest that people who research and side-project tech stuff are universally cannon fodder or have otherwise negative loser-y properties. I certainly don't believe that as I do it myself...
What I meant to suggest is that there is a certain cynical undertone in an organization where 'work is also my hobby' is a disproportionately desirable line item in an interview. I was attempting to project that attitude rhetorically. Given your offense, I think the point was made, but maybe too subtly... It is an offensive attitude. To me it implies something negative about how I (and my time) will be valued.
This isn't to say anything about the (what I think is) natural 'starting a new job' period, where one puts in extra hours to get up to speed on the technologies being used and the existing code-base. That's part of hitting the ground running and being a good and productive hire.
These are not necessarily contradictory positions.
Even if you work only 40 hours a week directly developing software for the startup, the independent time you spend self-educating and researching can often enable faster development.
It's really annoying to read replies like yours that systematically suggest all people who spend time researching and side-projecting stuff about tech are doing so because they have lot of free time or are cannon fodder. If you prefer to spend your free time gardening or brewing beer, that's fine. It's equally fine if I enjoy spending my own time learning about more tech stuff.