The discussion of Becker reinforces my belief that the discipline of Economics exists primarily to justify pre existing power structures by using assumptions which are convenient but empirically unfounded.
If the above reinforces your belief that "economics exists primarily to justify pre existing power structures by using assumptions which are convenient but empirically unfounded," then what exactly would weaken your position?
If you think that's what Economics does, you either have not studied it, or somehow studied it under a unique professor in a unique environment, isolated from reality.
Not to mention that your statement makes no sense at all, since if the power structures are already existing, then by definition, they are empirically founded.