Sort:  

They just have to be ‘professional’(no selfies). I think they don’t mind as long as it is a clear picture of the person. I’m not sure why that is the case though, passport styled photos would also make sense to.

It quite weird they need a picture on their CV, but I quess it's so they know it's the same person they are going to interview,

It's definitely not something I was (or am) used to. I think that in Korea looks are much more important that many other countries, for better or worse, looks can have an impact on your job chances here. As a teacher I was always asked to provide pictures (they even asked for pictures with friends and/or family).

Seems weird, something we're not used too, looks shouldn't matter it should be the persons work ethics, but maybe they have figured something out that other countries haven't.
It would be interesting to know the typical length of time it takes someone to get a job and weather looks can hinder you from getting one.