Likely copy/pasting a dictionary in the comments: how should we respond?

Question

Some questions (like this one) end up with comments which appear to have been copy/pasted from somewhere, and I'd guess from a dictionary.

While these users are trying to help, I see multiple problems with this:

1. it's largely effortless ["your answer is somewhere among this huge text you probably can't read"],
2. copyright/plagiarism issues,
3. comments are thought of as "temporary" (see below),
4. comments are not editable, nor downvote-able,
5. they may answer the question in the comments,
6. it can look like a total mess, sometimes requiring multiple comments,

What should we do in these circumstances?

Question: Likely copy/pasting a dictionary in the comments: how should we respond?

Comments are often described as "second-class citizens" on Stack Exchange:

Comments are second class citizens on the Stack Exchange network, not designed to hold information for all eternity
_{Why do I need 50 reputation to comment? What can I do instead?}

The help page explains what comments are for:

Comments are temporary "Post-It" notes left on a question or answer. They can be upvoted (but not downvoted) and flagged, but do not generate reputation. There's no revision history, and when they are deleted they're gone for good.

---

I haven't searched exhaustively, but it's not hard to find many, many examples:

• Obstructive amounts of text What is the difference between 本来 and 原来?

• Three comments in a row here: What's the difference between "现在几点？“ and "现在几点了？” and Difference between 不得不， 不免 and 必然?

• Four comments in a row here: what is the difference between 條 and 匹? and What is the difference in usage between the pairs 依然/仍然 and 依旧/仍旧?

  And the OP even complained:

  I was interested in 然 and 旧. Please don't spam
  _{Maria Efremova, 2017}

• Six comments here: Give further examples of morphological alternation patterns such as Verb/Noun (处 chu3 / chu4) and Active/Inactive Verb (好 hao4 / hao3)

• Here How to use 者 as "... one who is ..."? the author was told

  If you have questions or suggestions about how the community treats comments, please post a question on the meta site.
  _{Don Kirkby ♦}

  This was subsequently ignored with arguing in the comments here: Why is it 出差去 and not 去出差?

• More arguing in comments Difference between 必 and 一定 and Using xiànzài and zhèngzài in a single sentence and https://chinese.stackexchange.com/a/29449/8099

This really is an obstructive misuse of comments. I'm not sure why these are left unmoderated.