As an introvert, who also really likes people, I can say that it's sometimes hard to find the "sweet spot."
That was really nice of you to make cookies for them
The neighbor may have felt like it would be rude to not call and have some interaction. By the standards I grew up with in the 80s, something like that would warrant a stop-by the person's house to thank them directly, and probably a short, friendly conversation. (Is the neighbor older by chance?). We didn't have the Internet or social media then, so some of us are hardwired for direct conversations and an expectation of friendly chit-chat, particularly when something thoughtful and neighborly has occurred.
It's wonderful that you did such a kind thing, and modeled it for your kids
(But also agree to be alert to them seeing you as a softy they can use
)