After having my third interview with a company, this potential new employer asked me to attend a trade show on the company's behalf - without actually extending a job offer before the trade show. It may be used as a condition of employment.
This seems to me to be an unethical request. In addition, if my present company gets word that I was seen at a trade show representing a different company, this would be career suicide. The potential exists that I could lose my current job and still not receive an offer from the other company.
I am uncomfortable representing any company at a trade show without being employed by them. How do I effectively communicate this with the potential employer without risking a potential offer?