Why do bars serve wine only in the bottom third or so of a glass?
Answer From Expert Roger Bohmrich MW
In my experience, most bars tend to use a relatively small wine glass and fill it fairly close to the rim in order to give the customer the sense that they are getting their money's worth. Normally, a bar is not a setting for wine appreciation - unless, of course, you mean a wine bar.
Wine lovers realize that using a larger glass and filling it half full is generally preferable as it allows the drinker to swirl the wine so as to liberate and appreciate the aroma. I would say this is still not general practice in restaurants outside of the world of truly progressive, wine-savvy establishments. Thankfully, this is changing as America becomes more informed about wine.