This thread made me learn that strict followers of Jainism don't eat "root vegetables such as potatoes, onions, roots and tubers as they are considered ananthkay. Ananthkay means one body, but containing infinite lives. A root vegetable such as potato, though from the looks of it is one article, is said to contain infinite lives in it."

https://en.wikipedia.org/wiki/Jain_vegetarianism

Another reason the above page lists: consumption of most root vegetables involves uprooting and killing the entire plant, whereas consumption of most terrestrial vegetables does not kill the plant.

Perhaps the most surprising part for me: "Strict Jains do not consume food that has been stored overnight, as it possesses a higher concentration of micro-organisms (for example, bacteria, yeast etc.) as compared to food prepared and consumed the same day."

Western veganism and vegetarianism are not the same as in India.

Indian "veg" cuisine disallows eggs (unlike western vegetarian) but allows milk (unlike western veganism).

There is also a stricter form in which garlic and onions are disallowed, because they are said to inflame the passions.

There was a time when some Westerners believed similar things, which is how the world got corn flakes. And some other things I won't go into here.