So we used return to line for a bathroom break in 2016 at the Imagination theatre for the Pixar shorts (don't judge me).
We had just missed the movie startime and stood in the lobby for a few minutes before deciding to run to the bathroom before it started. I was passing a kidney stone, a not-uncommon occurrence for me since I have a chronic condition.
We told the cast member at the door, and he said it wouldn't be a problem because we still had 7 minutes or so. As we left, another castmember in the lobby walked over to him and she shot me a really unpleasant look.
We ran to the bathroom and were back in less than 5 minutes, and the guy cast member gave me a high 5 as we walked past him and said, "You made it!"
A short line of 12-odd people had lined up at the theatre doors inside the lobby by now, so we joined them. The cast member who had shot me the ugly look was ushering people in, but when she got to us at the end of tge line, she triumphantly (no other word for it) closed the doors in our faces and said the 2 of us had not made it in time.
I had never met or seen her before, and I'm always nice to people since I worked retail as a cashier for many years and know firsthand how awful people can be to service workers. I also know when people are being unpleasant just because they can, and she totally was.
The meaness of our bad interaction really put a shadow over our day, and we didn't go back to the movie during that visit because we didn't want to run into her again.
I'm worried about this new 'Return to Line' system putting the burden on line staff because of the abuse, but also because a cast member having a bad day could potentially take it out on a guest with a serious medical condition and deny them a pass for a break, with possibly life-threatening consequences.