It kind of does though; if I own a store and say that only people with hats can enter, then I'm free to do so. Silly? Yes. Legal? Also yes.
There are some circumstances where it's not legal, mostly centred around discrimination. Details on this differ per jurisdiction, but generally speaking you have a right to refuse customers.
To me it seems sending a http request is somewhere inbetween looking (legal) and entering (illegal if not permitted).
However, most important is that the web as a system makes positive interactions easy and negative difficult. We have already found some set of constraints achieving this for interactions in public city streets. But it's not obvious the same rules (that we have internalized) have the same effect in another medium of communication.
In most cases you have very limited ability to decide what other people cannot do. And other people has mostly infinite choices of what they can do. I never heard anything as broad as you said. What you said is like a person standing on the street with a T-shirt says "do not look at me more than twice" and claim it has a legal binding to the whole world.