I have about 4 years experience in the software industry. I recently resigned from current organization.
During negotiation I mentioned my salary difference with my colleagues doing similar work. My colleagues (With 1 year less experience) are getting paid about twice my current salary, probably because I did not graduate from a leading university.
I mentioned the discrepancy at many appraisals. I casually said "you will be able to replace me but you would have to pay at least 2 times the salary to a new employee" to my manager. Is this unprofessional? I argued "One should not give different salary for same kind of work".