Making Multiple Accounts

I know that making multiple accounts is listed againts the rules in the TOS. I suppose that alone could/should end this discussion. Still, I wanted to ask about the idea of making multiple accounts.

I know that abusing multiple accounts is the concern, such as knocking down your own gym. What if you were making more accounts that wasn't in an abusive manner though?

I'm not asking about whether I should be able to make multiple accounts or not. You don't know me, so you have no reason to trust that I wouldn't abuse it. It's the principle of the matter that I am asking about.

Suppose the accounts created never interacted with each other. They were never used at the same time (on multiple devices). I suppose you could argue that interacting with your friends could fall under abuse (for example, my main team is Mystic. If I wanted to knock down my sister's gym, I would be able to switch to another account and knock it down, since she is also Mystic). I always see people protesting multiple accounts when it is abuse. What about when they are used separate from each other?

One final thought, that wouldn't stop multiple accounts from being made, but is a related topic. What if players could switch teams, but it cost them a % of their experience? That way someone like my sister could switch to Valor, and not worry about having to start all over. It also would be less abused, as you have to re-earn a chunk of your experience.