Development projects are almost always team efforts. And, unfortunately, there's almost always one or two team members who aren't very good. Some of you folks that only work on startups with brilliant people might disagree, but in my experience most development teams have some bad apples who have let their tech skills rot, or won't try for some reason or another.
These people are going to have a tremendous time just writing halfway competent javascript (especially since it's probably not similar to their OOP language of choice). Suggesting they write code in an uncommon way is just begging for trouble. Most of the examples on the internet use semicolons, as do most of the frameworks. In fact, I hope that members of my future teams never see this javascript style guide or even know that it's possible to omit semicolons in many cases.
I'm quite sure someday soon I'm going to hear this over the cube wall: "Hey, GitHub doesn't use semicolons in their javascript so I won't either!" And then I will be very, very sad.