I suspect you slightly under-appreciate how ubiquitous sugars are in nature. Glucose and its close relatives are everywhere in plants. Cellulose, the main building material of plants, is polymerized glucose. A ton of various substances of plant origin are all pre-built to interact with sugars, and may have trouble interacting nicely with severely different kinds of molecules.

With relation to baking and frying, https://en.wikipedia.org/wiki/Maillard_reaction works with sugars, and likely can't work adequately with something materially different.