[anon2020dot00]

People get snippets from Stack Overflow all the time and usually there is no concern whether it is properly attributed or not.

I'd argue that people who open-source code expect other people to learn from it in a small way of snippets and that constitutes fair-use.

[foldr]

Code in Stack Overflow answers is explicitly licensed under a permissive license:

https://stackoverflow.com/help/licensing

Copying code samples from a copyrighted work for use in a commercial product is not fair use.