If you're entering a country, do its laws not apply to you until you've seen a copy of them? "Oh, sorry, no one told me theft is illegal here. Where does it say that? Oh, I see. Okay. I'll stop now. Thanks for letting me know."
If you cross the border without necessary documents, does that country have no right to detain you, simply because you haven't checked the laws?
Just because a website is visible and public doesn't mean its content is public domain. It just means that your first order of business as a user should be to check the terms of service. Sure, most people using a website probably don't need to--same as not needing to check a country's stance on murder--and so can just use the website as intended without violating the terms. But when you plan on using it in a way that might not be intended, and you don't check the terms of service, well, that's on you.
Country's laws are a bit different, simply because a country has virtually absolute legal power over its territory. Countries can and do punish people for breaking laws that one cannot feasibly know they were breaking. Does any human know all the laws in the United States? Would that even be physically possible?
There's some interesting science fiction opportunities here. When you open a connect to a site then all traffic over that connection is subject to the jurisdiction of the ToS for that site regardless of disclosure.
Also we don't even know how many laws there are in the United States for I'd say knowing the content is impossible.
That is not a good analogy. There is such a thing as reasonable expectations when visiting a website, so you do not need to read the TOS. Otherwise I could put "you own me $1000 for visiting my site" into the TOS. In other words, just clicking on a page does not constitute entering into a contract with the website. Registering and accepting the TOS does, but that still doesn't mean that anything in the TOS is enforceable.
But when you plan on using it in a way that might not be intended, and you don't check the terms of service, well, that's on you.
I don't need to check your terms of services if I'm doing something that I'm allowed to do by law anyway; the TOS cannot deny me those rights (they might, of course, grant me additional rights provided that I follow certain conditions).
If you're entering a country, do its laws not apply to you until you've seen a copy of them? "Oh, sorry, no one told me theft is illegal here. Where does it say that? Oh, I see. Okay. I'll stop now. Thanks for letting me know."
If you cross the border without necessary documents, does that country have no right to detain you, simply because you haven't checked the laws?
Just because a website is visible and public doesn't mean its content is public domain. It just means that your first order of business as a user should be to check the terms of service. Sure, most people using a website probably don't need to--same as not needing to check a country's stance on murder--and so can just use the website as intended without violating the terms. But when you plan on using it in a way that might not be intended, and you don't check the terms of service, well, that's on you.