There are people who not only quit the tourney, but make a huge deal about it (or disappear without saying anything to their opponent). Both of those slow down tournaments and are annoying to the organizers. Banning people that quit a tourney in a disorderly manner will help prevent them from doing so in the future.
in a disorderly manner (being indignant about losing, spamming in public chat, making a huge deal out of anything), sure, go ahead
but if they leave a confused opponent behind, it's TO's responsibility to resolve that issue, no matter who causes, and this usually takes a second to type: "your win", does it really slow down much of anything?
I am not against this due to personal issues, I haven't been very disruptive (I don't think) to PvP events, but I am strongly against this.
Elements community seems to be more and more looking like an idealistic utopia, where everything is super-imposed
if TOs are too annoyed by having to have to answer some competitor's questions, step over, and let those who are willing to do it, when you signed up for the job, you have to have the mindset that you will need to do such things
I am sure it gets annoying, but banning ppl like this isn't the best way to prevent it