Virtually every dictionary clarifies that theft requires intent to deprive the original owner from using the stolen item, which is incompatible with the act of making a copy.
As gp said, your points are valid, but you're using a word incorrectly. Just use a different word so as not to have dictionaries disagree with you. Copyright infringement.
Society being in a lurch between how we handle our physical goods and our digital goods is a very important subject that is going to get ironed out over the next few generations I'm sure.
That doesn't make it not theft, even if its' really easy to do.