I think I should probably have clarified/added some additional info to my earlier post.
In my experience (and my general view), having worked in the HR area, people who log things "just in case" are usually genuine and the complete opposite of troublemakers. They usually have a significant (or significantish) issue and don't want to rock the boat and be perceived as a troublemaker by making an official grievance. The trouble with this, is that if you take it on face value (and do nothing as requested) the issue keeps on happening/festering/making people miserable.
"I just want to log this just in case" conversations often flag an issue like bullying or unpleasant behaviour. In the few cases I've dealt with "I don't want to take this further, but" conversations, it's actually ended up resulting in dismissal (of the accused, now the whistle blower!) down the line because it was part of a wider pattern of behaviour that nobody wanted to speak up about. The office environment became a much happier, collaborative place as a result.
So I guess the question I'd ask is, why are you raising the issue if you don't want anything done? Deep down, is it because you're worried about repercussions (if so, it's HRs job to protect you)? Is it because you're worried about being seen as petty (if so, are you being petty or are you actually seriously bothered by something, in which case it's a valid concern to raise)? Etc, etc..