How will the passengers respond?
By saying "Does that stand for 'Bad Liars Murder'? They can't kick you off the plane for that, can they?
Pretty limited, I think. If you walk off the plane, you will face a $300 charge to re-ticket and be late to wherever you are going. Probably the best thing is to bombard the executive staff with calls and letters and emails if you encounter such a racially-charged pin on a worker.