why do we call it fill?

I'm going to guess that this was entirely a joke, and I think in that case it's better suited for Memes & Games.

Nah, just a couple people who freak out and shut down because they can't play their first blood or feed Riven. A lot of people though see they get autofilled and think "oh, I'm support this game" and that's the end of it. Not every autofill needs to complain in chat about it because we know it happens, but playing support every now and again is better than dynamic que.

I don't why when people get auto filled, why do they not ask if they can swap positions? I've seen very few instances where people do not swap, if they don't it's usually because they are bad at they role you where auto filled.