I noticed a request for an item that I had bought recently but hadn't gotten round to uploading, people were offering lots of points for it, I am not greedy so I posted a comment saying that I would post it soon, and didn't need the points.
It didn't cost people the 100s of points they were offering.
What got me was not one person actually thanked me. I could have taken all their points and still uploaded it. But I didn't.
I try to give back to this site where I can, but next time I might not be so generous.
It doesn't hurt to say thank you.