—especially when a first timer needs a clear. Nothing is more annoying than having to wait 20 minutes for the queue to pop and someone withdraws and then having to wait yet another 20 minutes for the queue to pop again when I should have only had to wait 20 minutes, but because someone withdrew immediately or was afk when the queue popped, another 20 minutes of wait time is often tacked on.
There is nothing hard about staying at your PC or PS while you are in queue. I can remain at my desk while in queue so can everybody else.
It is not that hard to hold it if you need to use the bathroom. I can hold it in for an hour or so. It is not like you will be in the dungeon for more than an hour unless you are in an extreme practice party or whatever or you get a party of all people who level jumped that shouldn't have and don't know what they are doing.
If it is really that of an emergency, ask someone to watch your queue.