I have to say I've found the point of view that this guy is creepy because of his approach to the OP interesting. It didn't come across that way to me at all - I just figured he was used to a more friendly or forthcoming type of neighbor relationship and was just being upfront and honest with the OP and wanted to know if he had done something to offend her.
Maybe I'm naive?
It's possible that different posters are referring to different types of "creepy." Being used to more friendly neighbor relationships
is fine. Wanting
a friendlier relationship
with your neighbor is fine. Asking "Have I offended you?" because the polite, reasonably friendly neighbor isn't as warm and fuzzy as you expect isn't so fine. On one extreme, he could be intentionally trying to manipulate her into being friendlier than she is comfortable with, which is creepy. On the other extreme, it could be pure obliviousness that anyone might not want to be best friends with their neighbors right off the bat. And IMO, that level of obliviousness is pretty extreme and could be creepy in its own way.
For comparison, I know someone who seems to be a truly well-meaning person*, but appears completely unable to grasp the concept that not everyone likes the same things he likes. For a while, we were both part of the same club, and I eventually dropped out purely because of him. He is awful to deal with and has very little sense of boundaries. He'll listen to an entire discussion of why the rest of the group unanimously thinks we should do something a particular way, forge ahead and do things his way, and appears to sincerely think that everyone will be happy with that, because it's the "right" way in his mind. I am completely confident that he is not romantically interested in me, but his sheer obliviousness to the wants and needs of other people can still be creepy as hell.
I doubt that the OP's neighbor is anything like the guy I described, but I don't think "creepy" is limited to guys with bad intentions.
*Either that, or he's breathtakingly good at playing the role of well-meaning guy with no social skills and chooses to do so 24/7