Right or wrong, I really can't think of a tomato as anything other than a vegetable...

I know it's a fruit cuz that's my field of work.

On the surface it is more like a veggie.

When you cook it, it 's more like a veggie. It's no longer sweet when you cook'em[or heat'em]. There's seeds in them [like the bell peppers too] but I don't think that makes it a fruit.

Some people want to call it veggie becuz it's more popular sounding.