Although knowledge surrounding the obstacles omnivorous consumers face when substituting meat products with plant-based alternatives has increased dramatically, less is known about their perspectives on plant-based alternatives to dairy products. Here, these perspectives are assessed in two survey-based studies. Study 1 (N = 175) adapts an existing scale (the 4Ns of meat consumption) to dairy products in an effort to identify similarities and differences between rationalizations for meat and dairy consumption. This 16-item scale quantifies four factors (Natural, Necessary, Normal, and Nice) describing common rationalizations for meat consumption. The results revealed that the 4Ns transfer well to the dairy category, and that endorsement of dairy products as Nice was the strongest predictor of dairy consumption, relative to the other 3Ns. This is further supported by evaluation of consumers’ own qualitative descriptions of why they do or do not consume meat/dairy products, where “taste” was the most frequently used word in both categories. Study 2 replicates the relationships between dairy 4Ns scores and reported dairy consumption found in Study 1 and builds upon these results by showing that 4N score could accurately categorize consumers as frequent (N = 192) or infrequent (N = 210) consumers of plant-based milk alternatives (PBMAs). Differences in consumers’ expectations for the sensory characteristics of cow’s milk and PBMAs are identified, and the impact of rationalization (total 4N score) on the likelihood of expected sensory attribute associations is described. The role of rationalization in shaping sensory expectations and impacting dietary choices, in particular resistance to adopting PBMAs, is discussed.