She's extremely lucky she heard that. Imagine if she had started dating him, and then due to knowing him for so long, had got quickly married after high school. The dude would have, with 100% certainty, hurt the family finances by gambling and other reckless behavior. You can tell by how casually he lied to her about his grandpa being in a hospital and wanting to bring him fruits, yet he only wanted to hit the arcade. It's the kind of ruthless lie that reveals his true nature. After all, he knew the girl, a childhood friend, knows his tough family circumstances and would thus be sympathetic if he told something happened to his family members. On the other hand he apparently never pays back what he borrowed from her previously, which is another telltale sign of his true nature. I'm sure she has heard plenty of times all kinds of excuses and promises.