Background: Individuals with Prader-Willi syndrome (PWS), a chromosome 15 genetic disorder, often have a significant preoccupation with food and problem behaviour related to food seeking is often prevalent. Methods: In the present study, we compared how individuals with PWS responded on a survey regarding the acceptability of food in various locations that varied according to degree of appropriateness for human consumption (e.g. food on a plate, food in a garbage can). For a subgroup of participants, we observed how they actually responded when placed in a room with food items placed in the same locations depicted in the survey. In the first part of the study, three groups (25 typically developing individuals, 7 individuals with intellectual disability (ID), and 19 individuals with PWS) responded to a visual survey to determine the degree of acceptability of food items in various locations (e.g. on a table near a hairbrush, on the floor behind a toy box, in a trash can). In the second part of the study, these food items (popcorn, jelly beans) were placed in the 12 locations described above. Nine individuals diagnosed with PWS (deletion type) and three individuals with ID were given some break time in the room for 15 min. The amount of food consumed, the time spent food seeking, and time spent interacting with materials were measured. Results: Results of the survey indicated that the PWS group differed significantly with regard to how they responded on the survey from the typically developing group, but did not differ significantly from the ID group. Results of the food seeking observations indicated that only three individuals with PWS ate a significant number of items. The three individuals did not differ from the rest of the group according to IQ or compulsivity score; however, they had significantly lower body mass index (BMI) scores and were younger than the other participants. Conclusions: The findings from the survey indicate that individuals with PWS are able to discriminate the appropriateness of eating items in more or less contaminated areas; however, the amount of time spent seeking food and the amount of food covertly consumed appeared to depend more directly on age and BMI.