Can demons be vegetarians?

So i'm rewatching the anime and am at the point in the harvest festival where they mention that balam managed to win his harvest festival without injuring any students or animals, so does that mean demons can be vegetarians since they could theoretically gather food without killing any animals? I always imagined demons as compelled carnivores kind of like lions and tiger literally unable to survive without meat. Does it mention anywhere if balam is a vegetarian? Because I'm guessing if any demon would choose not to eat meat it would be him and if he isn't one then I'd assume its not dietarily possible and they can simply have about 5% of there diet be plant products like house cats, so not a large part of there diet.

Any lore info or speculation is appreciated 😊