Um did you even read my response beyond the first few words. How can you possibly have high customer service skills without work experience and extra curriculars, unless I'm missing something.That is something totally different. Your scenario doesn't accommodate emplyoyers who reject people with high marks, it focuses on employers rejecting people with low customer service skills. Whether you have high or low marks, you are still going to have the same customer service skills.
If you have nothing else but high grades you might struggle to secure a job in a client focused organisation (for example an accounting firm.) If you have high grades + other stuff ie work experience + extracurriculars you'll be fine.