It is almost impossible to understand why an employee would advance fees for customers of his/her employer. You don't indicate the type of business but I'm not sure it would make any difference. To specifically answer your question, no.
The above is general legal and business analysis. It is not "legal advice" but analysis, and different lawyers may analyse this matter differently, especially if there are additional facts not reflected in the question. I am not your attorney until retained by a written retainer agreement signed by both of us. I am only licensed in California. See also avvo.com terms and conditions item 9, incorporated as if it was reprinted here.
I agree this is probably illegal, but the manner in which it is handled can mak a huge difference. Even if it is ilegal to fire or discipline you for protesting illegal pay practices, the law only provides a remedy after the fact. If your employer fires you, illegally or otherwise, you are the one without a job in this rotten economy. You may want to work with an attorney with whom you can develop a strategy to better protect your job -- though there never are any guarantees. An employer who breaks one law may also break other laws.
To find a plaintiffs employment attorney in California, please go to the web site of the California Employment Lawyers Association (CELA). CELA is the largest and most influential bar association in the state for attorneys who represent working people. The web site is www.cela.org. Click on "Find a CELA Member" and you can search by location and practice area. Many CELA attorneys represent clients throughout the state.
I hope you can resolve your situation and wish you the best.
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