If I see someone wave or honk at me, I wave back. Most of them are strangers to me because far more people know who I am than I know them.If a stranger waved at me where I live I would absolutely feel creeped out.
A year after I moved to my current location my brother bought the place next to me. Shortly after that I came home to a note on my door inviting me to a picnic by someone that I had no idea who it was. I asked my brother if he had gotten a similar invitation and he said no but then he pointed out that he didn't have a backhoe sitting in his backyard.