I agree that this is unprofessional behavior. Was there retaliation? Did she disallow deductions because of what you ate, etc? I understand feeling like you are being targeted or retaliated against, but you haven't specified how you feel that she treated you differently as far as the deductions are concerned, than she would any other taxpayer. If she went through the questions, and you didn't meet the requirements regardless of your food choice, your argument is merely that she was unprofessional in doing her job. You can always ask to speak with her manager, and her manager might say something. The reality is, there is no reason for those statements. They don't move the ball forward for the IRS.
You can sue anyone for anything, but there's no harassment here, and you haven't noted experiencing any damages.
Yes, it was definitely inappropriate for the agent to comment on your eating choices, but it's not grounds for a lawsuit, and you haven't provided any facts about any retaliation.
Avvo doesn't pay us for these responses, and I'm not your lawyer just because I answer this question or respond to any follow-up comments. If you want to hire me, please contact me. Otherwise, please don't expect a further response. We need an actual written agreement to form an attorney-client relationship. I'm only licensed in CA and you shouldn't rely on this answer, since each state has different laws, each situation is fact specific, and it's impossible to evaluate a legal problem without a comprehensive consultation and review of all the facts and documents at issue.
Yes, I agree / not actionable. But after audit is done, and you are back in compliance, you can certainly make a respectful complaint to the auditor's manager.
Please note that this is not legal advice, and should not be relied upon as such. Always consult with a competent tax professional to discuss your specific situation!