The Metaverse is often portrayed as a novel context for digital consumption, but this paper argues that its deeper value lies in its potential as a behavioral observatory. By loosening four traditional consumer constraints of identity, time, space, and financial access, the Metaverse enables researchers to examine consumer behavior under conditions that are difficult or impossible to replicate in the physical world. We define the Metaverse through the lens of constraint relaxation, distinguishing it from other digital environments such as social media, gaming, and augmented or virtual reality. We then examine how these relaxed constraints reshape marketing research across consumer data analysis, experimental design, and privacy governance. For instance, the fluidity of identity in the Metaverse, where users can adopt multiple avatars, provides a natural context for exploring identity construction and expression. Nonlinear temporality and borderless spatiality challenge sequential experimental designs and traditional geo-segmentation approaches. Relaxed financial constraints alter how consumers perceive value and engage in aspirational consumption. In conclusion, we synthesize current knowledge and forward-thinking analysis to propose a research agenda. Rather than treating the Metaverse as an endpoint for digital innovation, we position it as a methodological and conceptual tool for rethinking marketing theory and generating insights relevant to both virtual and physical contexts.