From the chemical point of view, the glass is an inert material. Does not interact with foods that contains, and then protects the flavor of the content in foods and drinks such as no other material is able to do.
The glass does not need additives to protect the freshness and aroma.
That's why anyone who loves the art of cooking, and processing of foods, from great chefs, the proponents of good food and food producers prefer.
The glass is preserved, and you keep the flavors as they really are, and being able to be said that 'everything to taste.