I'm a vegetarian, but I don't like bell peppers, kale, quinoa, raw tomato, mustard, dill, vinegar, and mayo (vegan or not). I like apples and spinach but they do not like me.

This still leaves plenty of options for a sandwich, but then I have to worry about buying produce and keeping it fresh. The more variety in what I buy, the bigger the hassle.

Augmentmenting a smaller amount of fresh produce with (freezable) fake meats gives me a lot more options, not to mention the benefits when I eat out (take away bell peppers and most veggie options on the menu vanish)

Plenty of vegetarians/vegans agree with you. Plenty of us do not.