Because some people dont have the mindset of yhe biological(the scientific mindset) and culinary(the common mindset) seperate.
Tomato is common for it because its a fruit biologically and a vegetable culinarily.
Other examples of it in common practice is "berries".
Culinarily, strawberries and raspberries are berries, and bananas arent. Biologically its the opposite.
I have actually done that… well, I had a medical problem with swallowing and I was making shakes of all kinds of savory foods. Sorta like smooth soups… chicken and broth, roast beef with rice and potatoes, beans with salsa and cilantro… pretty good actually. I kinda miss the chicken milk.
Tomato toxic when it green, but delicious when it red. Creeping nightshade toxic when it green, but has anyone even tried it when it red? Probably delicious.
From just some cursory googling it looks like they are toxic when raw, but frying them neutralizes the toxicity. That's probably why you've never noticed!
Potatoes fall into this category too of both delicious and nightshade fun. So tastes great like anti freeze but it takes a lot longer to finally get you.
I have eaten American Black Nightshade berries before. They taste like tiny tomatoes mixed with blueberries. I haven't had a full smoothie of them before though