There isn't a doubt that using wine glasses when drinking cheap and expensive wine adds a lot of value to it.
For the casual wine drinker, using wine glasses for drinking wine may do so because it is the norm. Also because wine simply looks better in wine glasses than just being drank from tumblers. However, wine glasses are designed the way they are for important functions. The three main parts of the wine glass make it an ideal vessel for optimizing the value of wine, especially with expensive ones. The base otherwise known as the foot of the wine glass doesn't really have a distinct purpose other than to keep wine glasses standing. But technically, this function alone makes it an important part although not something that makes wine glass special compared to other vessels containing liquid.
The stem of the wine glass seem superficial to most people. Some even assume that it is there to make wine glass look fancy and have the hands hold the glass daintily. It may have that effect visually but the stem of the wine glass actually serves an important function. It is indeed meant to be where the wine glass should be held, but not to make it look fancy. The hands generally have a different temperature with the wine inside the wine glass. The stem is there to prevent the hand from touching the bowl of the wine glass, so as not to alter the temperature of the wine.
Tumblers or any other liquid container without a stem are out of the question. And here’s an example; the stem of wine glasses might seem irrelevant but this feature actually serves a necessary function to optimize the quality of the wine being tasted. Stems are allotted for the fingers so that the hand wouldn't have to touch the bowl of wine glasses. Contact of the hand and the wine glass bowl will inadvertently alter the temperature of the wine it contains. Meanwhile, keeping away from those that are made of thicker glasses is advised. These thick glasses make wine look cloudy. Although may be just about appearances, there isn't any doubt that an elegant wine glass enhances the impression of anyone who is about to drink the wine it contains.
Red and white wine glasses as an example have common characteristics for their bowls. The common denominator is that their bowls have their widest part somewhere in the middle. This is to allow red or white win to have a large surface area exposed to air to bring out its great texture through aeration of the tannin contents. The tapered rims of these wine glasses are meant to minimize the escape of the aroma which is the byproduct of the aeration. There are some wine glasses that have wide bowls but flare out to the rim of the bowl. This may be great for aeration but definitely discouraged because the wine taster will never get to feel the nip of the wine's aroma while drinking.
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