Oh wow, what the hell. I'm not actually familiar with C++ (just with Rust which gets similar reactions with the ampersands), but that's insane that it just copies shit by default. I guess, it comes from a time when people mostly passed primitive data types around the place. But yeah, you won't even notice that you're copying everything, if it just does it automatically.

And by the way, Rust did come up with a third meaning for passing non-references: It transfers the ownership of the object, meaning no copy is made and instead, the object is not anymore allowed to be used in the scope that passed it on.
That's true, except for data types which implement the Copy trait/interface, which is implemented mostly for primitive data types, which do then get treated like C++ apparently treats everything.