Yes.
>Hacking a server you don't own is handling someone's property without permission.
I meant handling in the most literal sense: manipulating something with your hands/body. Sending a message to someone/something isn't handling them/it in that sense.
> When I host a web service, I grant the public permission for very particular kinds of access to it. I do not grant the public permission to try to break into it.
Morally speaking, I do not require your permission to do something that doesn't physically involve you or your property. The only relevant physical involvements here are between you and your ISP, and me and my ISP. Anything else is abstraction.
Under your permissions idea, I can go out and say "I grant the public permission to look at my face but not to say hello to me."
> Your understanding of the world is incompatible with centuries of civil, criminal code, as well as millenia of common sense.
Your understanding of the world is incompatible with freedom and justice.
> Intent absolutely matters. Consider why mens rea is a thing.
Something being a thing doesn't justify it morally. Slavery is a thing, you know? Murder is a thing, etc.
> I take it you also don't take issue with people stealing the contents of vending machines, either? After all, there's no possible way to infer what the implied contract of a vending machine is! Sure, everyone with the intellectual maturity of a five year old understands that you're supposed to put money in, in exchange for its contents... But it's the owner's fault that if I happen to tilt it over a certain way, stuff comes out of it - without me putting any money in! I'm just manipulating it in a creative way!
In a world with laws that make sense, it would be necessary to explicitly define the contract, because otherwise everyone would be handling someone else's property without permission. Simply state in the contract that people have to pay $x in order to take out their goods.
If the contract says "use this machine at will and take its contents". Then yes, you can tilt it all you want, who would have thought?