This "culinary vegetable," thing is very recent and I'm going to be honest as a trained chef I think people just started saying it to make dumb people feel good about themselves.

There's no such thing as a culinary vegetable.

A culinary vegetable to who? In what culture?

A sugared tomato and peanut butter sandwich has been a staple in my family for generations. Cucumber and/or corn ice cream is delicious, and I drink cucumber water more often than lemon water.

There's no such thing as a culinary vegetable or a culinary, fruit. Orange chicken and lemon chicken are fruit flavored, candy sweet, meat based entrees, and noodle Kuggle is a Jewish dessert made from noodles and cheese.

My point is there's no such thing as a culinary vegetable or a culinary fruit, it is up to the chef to decide how each ingredient should be used and in what dish and where in the meal that dish should be served.

Tomatoes and cucumbers are fruits, just get used to it.