Ya, I know, i didn't pick up the cosplayers the first time either. Then it just sorta hit me.
Actually, when the live footage started, I thought the movie was going to end at the end of those shots. Like that Simpson's episode where Homer comes into the real world. At it end with him going into a bakery.

You know, something to make you say: "ok... that's it, where the ending?", but then it came back to Shinji and Rei. And I was all "Phew! That wasn't the ending".
And, I think Shinji have some obsession with strangling Asuka.

He likes doing that.