well you know just googling "obesity hearing loss" bring up a whole host of articles about the association between the two -- especially in women. Look, when doctors hear hooves they think horses not zebras.  They don't have tricorders they do the best they can given the evidence in front of them.  Given that losing weight it literally the safest and most non intrusive treatment for a variety of ills they will ALWAYS suggest it because they are obligated to do what they think is best.