Just because you can do something doesn’t mean you should. Just because you can make an HTTP request doesn’t mean you have a right to do whatever you want with that data. You may not agree with that, but that’s what at least US law outlines.
There are plenty of fair use exemptions to copyright. That said, US law is not the highest of moral standards to aspire to. Especially US copyright law. We've been flaunting it online forever, because it's obviously ridiculous and still hasn't caught up with what's fair and equitable in 30 years.
If you're staying within the boundaries of fair use, you only have a Terms of Service to contend with. What you want to aspire to is meaningless versus what the law of the land is (which is what is enforced). That is my point. I don't disagree that most first world copyright law is overzealous and in a lot of scenarios, unreasonable.