Traditionally, cups have been the primary artifact through which beverage consumption has been inferred or defined, regardless of the numerous other artifacts that may be involved in beverage production, preparation, and service. Conversely, not all cup-shaped artifacts were intended to be used as drinking vessels, nor were all of them necessarily intended to contain a liquid. For the Maya Classic period (a.d. 250–900) decorated cylinder vessels in particular, this paper shows that the residues of their former contents do not agree with epigraphers’ interpretations of what have been taken as self-referential statements about their contents and uses. This disparity between expectations and data indicates that we have misunderstood both the vessels and the text, and perhaps that we have failed to recognize one or more classes of vessels. The research presented here suggests that we need to rethink the generally accepted interpretation that all cylinders were drinking vessels and that those that are currently referred to as “chocolate” vessels were never used for the consumption of liquid cacao beverage. These results provide a new context for interpreting the use, function, and purpose of these vessels. Methods drawn from both the natural and social sciences are used to relate archaeological materials, residues of their ancient contents, their hieroglyphic texts, ceramic imagery(/iconography), and past behavior. This diversity of methods accentuates that combining data from all these sources constrains the interpretations of each, and shows that our initial expectations about vessels with hieroglyphic tags have been overly specific. Determining the functions and uses of these vessels is not as simple as we have been supposing, but distinctions that prove to be relevant give us access to more complex systems of cultural practice.