It may be that a lot of people are like myself and really crave a heavy paper for several reasons, including the physical safety of the heavy sheet, from tearing, creases, being stained through with unintentional contacts with pens, liquids, etc.
Heavier prints are usually preferred by many people, often without the resources to dry mount or have a print dry mounted for themselves.
In this area, I am in need of verification, but thin papers might have a lesser 'depth' of silver emulsion or light reflection, similar to the depth of light penetration down into a well painted oil paintings made with transparent oils, where viewing light reflections from beneath paints cause the light to appear with greater "luminescence" which brightens colours and the introduced depth of field from a bright ground.
I also like the way heavier papers, especially Fiber Based Papers, lie on the easel and more precisely allows the application of colours, which in traditional photographic (pre-Coloured films) were colorized by, again, by Marshalls Oil Colours.
There are other reasons for my preference, but let others here edify the rest of us on their reasoning and choices.
Cheers.