There is a 3rd reason and you actually alluded to it in your post. You want something that you find attractive, but you can't afford or don't want to spend the amount it costs to purchase the original.No, I honestly don't understand it.
In my mind, there are two reasons to have copies - 1) to trick people into thinking you have the real thing, which is just sad; or 2) to pretend you have the real thing, which seems childish.
I get that it's not that simple. Somebody raised the example of a real painting vs a print. I do have framed prints in my home and I recognize that there's an inconsistency with that and with what I said above. So I know I don't have this all figured out perfectly. But I stand by my statement - I don't understand why people would want to play with copies because to me it feels either deceptive or childish. It's probably the same reason why I never cared for fantasy chips. Why do I want chips that pretend to be from Casino de Mexico? There isn't even a Casino de Mexico! I'd rather just use chips that say Fun Nite, and hope they're right. And it's the same reason I'd rather use starbursts for fracs than relabel something as a pretend frac.
Believe me, I understand that my thought process here is a little twisted. But I'm just being honest - I don't see the appeal of copies.
So, in fact, you DO understand, because you've done it yourself.