contracts and laws
... I can't sell you a couch with a piece of paper under the cushion telling you that you agree not to use it for sleeping on. Only copyright law really binds what I can/cannot do....
You are wrong here.
The difference is only that the EULA is a contract and the Copyright law is a "law." You are right in that the copyright laws are the only "laws" in play, but not that they are the only legal binding agreements.
The contract is still the contract and while you likely won't get
arrested for breaking it, it still binds what you should/shouldn't do.
You are maintaining that the only thing you have to worry about to
"be in the right" is the copyright, but you are still a dick if you break the EULA. Still equally "in the wrong," and eminently sue-able.
You are mixing up the fact that you probably won't be arrested or sued (or ostracised by your fellow humans), with the idea that this would be an okay thing to do. It's the classic, modern,
"if they don't see me, it ain't illegal" argument and it's totally specious.
It's pretty clear when and if you should purchase a copy of Tiger or Leopard and they are both fairly inexpensive as well. Apple has set it up so that you can do what you want of course, but don't intimate that there is some kind of moral argument for your position because there isn't.