Any survey will probably throw up responses according to the questions asked, how the questions are posed and the demographic of the population surveyed. In other words leading questions to a particular sector of the population will provide the answers required.
Of course you will always get a few 'bolshies' who will do anything to slew the answers but by and large, if the questions are what you expect to receive the answers you expect then that is what will happen. People generally tend to follow the herd, understand the innuendo, and respond accordingly.
An interesting exercise, nevertheless, and thanks Jock for your efforts.