Your hypothetical thinking is very possible; From what I know, hypnosis can be done in different manners and your consent is not always needed. It is also possible that if you are hypnotized and told to forget about the incident totally by the hypnotizer, you will most likely not have a knowledge of whatever you did. The best thing is just to hope and pray for you not to cross lanes with people who use their hypnotic skills for criminality, so we don't become their victims.