Recently I've been answering a lot of questions, and many people have corrected me in the comments (thanks!), but I was wondering if I can add their comment into my answer without crediting them.
If the comment was about a trivial matter like a typo then perhaps not acknowledging the originator is acceptable. If the comment was a substantive one then you are obliged to attribute it or run the risk of being accused of plagiarism. In that case rollback the edit. If this leads to an edit war then flag for moderator attention.
I several times both here and on law.se have edited an answer by adding something like:
As a comment by user ABC points out ...
This can be useful because comments are subject to deletion or to being moved to chat, while if their substance is incorporated into an answer (or a question) it is more likely to be preserved. Also it allows me to respond to or expand on the point made in the comment. As to acknowledging the poster of the comment, it seems to me only right and honorable to do so, and there it little effort or problem involved.
I will not take a position on whether the license we use requires such attribution, although it is at least arguable that it does. But it is IMO good practice, to be encouraged. I cannot see why anyone would edit to remove such an acknowledgement, and I would think such an edit should be rolled back unless other positive changes were also included.