This is a natural reaction to the spate of 'dating for free food' stories. The transactional nature of modern relationships has thus far been one sided. Kevin is simply forcing them to say the quiet part out loud.
The reactions are funny to me tho, I will say, cuz the rule used to be, you went on lunch dates with men you wasnt really feeling like that, evening dates- more expensive- were reserved for those you actually might fukk. He's repeating back to women the guidelines they themselves had set and everybody mad.