>Because you're POSTing them to a server?

How does that change anything? The HTTP protocol is just how I communicate with the program, just like how the USB protocol is how I communicate with the word processor. The dividing line is when the message crosses computer boundaries? Then it should also be illegal to write "I am an FBI agent" in a text file and upload it to Github.

>The same way you can't type everything into Google.

Who says you can't, physically or legally? Maybe Google will refuse to fulfill some search requests, but that's a different matter from it being illegal.