There was a human study in the 1920s by Clara Davis where they followed a group of children in self led eating habits. They offered a range of healthy foods each day and let the kids choose what they ate - generally kids fed themselves a healthy diet with appropriate portions as long as the food offered was healthy. They would even eat fish oil voluntarily and maintained good vitamin D and omega 3 levels.

Now the author never had the opportunity to try it with processed foods or junk foods, so this may not hold true when items specifically formulated to keep you eating come into play. However, it’s entirely possible that the crocodile in the image has some instinct that drives it to eat a healthy diet. Or you’re correct, maybe it is playing and using the pumpkin as a toy, but it is unusual that it would consume it then