A UI/UX Designer/Engineer does not inherently require programming. In many startups, it does, as does wearing many hats. But if they're looking for someone to program, it should be outlined in the responsibilities. Knowing "HTML/CSS/JS" is different than building an entire application (just an example).
Not only that, but the line "Experienced with Object Oriented JavaScript and modern JavaScript libraries such as Ember, Backbone, or Angular." was placed under "Preferred Qualifications", which to me says "desirable but not necessarily required". If that's not what they meant, they should have clarified the importance.
My personal opinion is that if a job wants you to build stuff, they should outright say "You will be responsible for developing and maintaing a code base, in addition to designing and lending UI/UX expertise" rather than just loading a job listing with keywords.