Yes, there is such tradition. I remember one of my maths professors at the uni 25 years ago complaining about "those people that "use a model to develop their r

Yes, there is such tradition. I remember one of my maths professors at the uni 25 years ago complaining about "those people that "use a model to develop their results and then hide the model when publishing them". I think that there are multiple reasons, not only trying to be "fancier". One important one is of presentation style. Some traditions (for example, Bourbaki) insist in conceptual purity and minimalism, presenting the most abstract concepts in its distiled form. Hiding "unnecessary" details is an objective on its own in that tradition.