I disagree. It depends on the job. Of course, if I hire a salesperson or for any role which involves negotiations with parties outside the company, I will gladly pay extra for a good negotiator. Therein lies part of the value of that person for the company. If I hire a back-office engineer or for any other kind of job that does not involve negotiations with external parties, I will not. Paying someone for skills which are not of value to the company is not only unfair to others who bring the same value to the company, but outright stupid.