Well, copyright does prohibit redistributing the scraped content. And that is what all 3rd party content scraping services essentially do. That violates copyright law in quite a few countries. If you scrape with your own tools, own servers and use it only within your company, I would think it's a different legal matter.

No, it's not "by law" public, or could you cite a few laws for that, both US and EU. Would appreciate that.

It is public because the HTTP standard defines it as public, and, if you claim to use this standard, its definitions apply to you (if you claim to support a standard, you have to accept that its definitions will be used in court against you)

HTTP directly says you should use authorization to make stuff non-public.

And third-party content scraping tools are NOT violating copyright law, as they do not redistribute it freely.

Otherwise services like Opera Turbo – which scrapes a website, removes cruft, compresses data, and sends it to your phone – would also break copyright law, and there is a nice exception for this case, under US law, it’s covered under fair use.

(Unless the scraping service makes your content accessible publicly – and even then, fair use applies usually, as in the case of pure archival like archive.org or archive.is)

You can have your content blocked from archive.org also by robots.txt - didn't check archive.is

Are you a lawyer? I am not - anyway, I can't really agree with that falls under fair use.

If I charge money to scrape someones site and then hand over the material in whatever form my customer uses - I am bound run into problems sooner or later.