The only way you can command a higher salary is to make your employer more money than anyone else who could do your job.
You make money for your employer by producing profitable goods that will be bought by his customers (who are also his employers).
This is why your employer is not your employer, but your employer’s employers.
Who’s Your Employer?
As the saying goes in B2B (“business-to-business”) industries: “Your customer is not your customer but your customer’s customer.” To be successful in selling your products or services to your customer, you need to make your customer successful in selling his products or services to his customer.