There is a particular kind of wine person who will tell you that the shape of the glass changes the wine. They are right. They are also missing the point.
A mug is warm, heavy, and holds a generous pour. It does not care about legs or tears or the angle at which you swirl. It cares about whether you finish the glass, which is the only metric that matters on a Tuesday.
The tyranny of the good glass
Wine culture has spent decades building a fence around pleasure: the right glass, the right temperature, the right occasion, the right vocabulary. Most people look at that fence and pour a beer instead.
Drinking good wine out of a coffee mug is not a rejection of craft. It is a rejection of the idea that craft requires ceremony. The wine is still the wine. The evening is better.