Question: Why is eating vegan food meritorious?
Answer: To be exact, eating by itself, of any food, is not exactly meritorious. It is the active choice of compassionate food in the first place, before consumption, that does not in/directly demand killing or harming of sentient beings, that is meritorious.
If eating vegan by itself is meritorious, eating a lot in one go should create much merits? Of course not, especially if powered by greed. However, choosing and eating animals (and their products) in any amount both create some negative karma, if chosen deliberately, as linked to the demand above.
Related Articles:
How Should All Aspiring For Buddhahood Eat & Drink?
https://thedailyenlightenment.com/2016/10/how-should-all-aspiring-for-buddhahood-eat-and-drink
The Five Contemplations To Remember At Mealtimes
https://thedailyenlightenment.com/2017/04/the-five-contemplations-to-remember-at-mealtimes
