You're right, it doesn't matter what shape the Earth is, as long as we know what shape it actually is.

To most people it really doesn't matter, as the shape does not affect their day to day life, but for others the shape has a direct impact on them, usually through their fields of employment. Aviation, maritime, communications and the environment are four areas that instantly spring to mind where the shape of the Earth has a direct impact.

I do agree with you that many flat Earth believers seem to be conspiracy theorists, although there also seems to be a fair number of religious types thrown into the mix.