I've tried to tell people about betta care a little, too... Unfortunately, it's not my place, and they won't listen to a teenager, but I just don't want them to know zilch like I did coming into this hobby. I have learned so much. I'm glad your neighbor got the right advice, though. He sounds like my dad, who argues that if they can live in cups at petstores, that's all they need. Thankfully, I don't get along with my dad, and knew better. My first betta started in a one gallon bowl that was heated with an undertank heating pad from a lizard. It was kept very clean, and I probably did /more/ than the recommended water changes. But of course, soon I conned them into letting me get a ten gallon tank.
It sickens me to hear of people who argue that if a fish/any animal can /survive/, it must be able to /thrive/ in the same circumstances.
EDIT: It's odd, I have three cats and not one of them bothers with my fish. They don't even seem interested in watching them, but I have caught them drinking from them.