We also find the Wiktionary definition [1]:
> One who does not contribute or pay appropriately; one who gets a free ride, etc. without paying a fair share.
Which I believe is a bit more generic (giving back might not be the only way of being fair).
> You may think of that term negatively
But the term carries a negative judgement, what's the point of this term otherwise? Without the judgemental part, you'd just say "using for free" or something.
The whole question is: is it fair to use open source software for free?
And I believe it is. Actually, this is stronger than this: I believe people should feel free to use free software for free, and should not be looked down for doing so. This is key for freedom 0 to be an actual thing. (I'm not set in stone in this position and would be happy change my mind on this though).
The notion of "giving back" can be discussed. I believe it is fair to get stuff from Person A for free and then helping B for free (later or earlier), in the hope that some person P will eventually help / have helped Person A for free for instance - this has the potential to provide everyone with a strong, helpful society and it would be even more enjoyable and reliable than a society that enforces pair to pair transactions.
Indeed, if someone always takes stuff for free and never contributes to anything, I would find this unfair (unless for some reason they can't contribute back, because of a disability or something). I would call this freeloading. Society cannot work like this. But you need the bigger picture to assess this.
When you start to try thinking about all this, the concepts of giving back, fairness, etc, it gets quite complicated. You also need to take in account the way society and the economical system works as a whole. What are the incentives, the motives, etc?
Basically, qualifying someone as a "open source freeloader" without context just because they use freedom 0 without paying is quite bold and might not be fair.
What if a company uses MinIO for free but provides some nice open source software?
Just don't judge someone too fast.
[1] https://en.wiktionary.org/wiki/freeloader