In Aaron's opinion a gesture wasn't much of a gesture unless it was meaningful, so her 'gesture' sounded more like a slight than anything else. Besides, he wasn't even hungry. And didn't buying him dinner or something make it seem like a date? People bought each other meals on dates, didn't they?
And really the trick wasn't to keep people from thinking he was poor, it was keeping them from thinking he had money. You didn't get mugged on the subway platform if people thought you had nothing on you in the first place. Even if you rather dangerously kept a pocket full of cash on you most of the time. But that was neither here nor there.
"Whatever, I'm just saying, you don't want to do this half assed." He ignored the rest of what she said on purpose. He wasn't being defensive. Really.