Scanlation for this series is not a paid thing. I just wanted to set that straight. We have our own real-life jobs (that are stressful as hell) so I hope you guys can understand that we only work on this on our free time from work unlike other groups who do scanlation while being students...
The answer to the question is that a tomato is technically the fruit of the tomato plant, but it's used as a vegetable in cooking. And besides, the japanese text had it as 野菜 which is technically vegetable in english.