No one answers you, because they are annoyed with your stupidity. You ask again.
What else would this be? Does this look like a cool place to hang out? This tiny, smelly, dark hallway? Does it look like the people standing in this row are talking to each other, or even that they know each other at all?
It requires exactly 1.5 seconds of analysis to determine that yes, this is indeed the line for the bathroom, and there’s no need to bother anyone with your maddeningly thoughtless, needless question.
Just a look around. Take a second to see if you can answer the question yourself. The answer is right there in front of you. Just because you are able to ask the question doesn’t mean you have to. It is the line for the bathroom.
Put it on the list.