I read this thread, oh my. Is it humor, bad planning, or BS. If it's for real things have indeed changed. In our many years of sexual adventures we never had a parade of men or women coming and going from our home in the middle of the night. Hotel or motel ring a bell. Discrete was the name of the game. We had children, loose lipped neighbors big problems.
No neighbor would know unless they were told. They might suspect but they would have to be told or see before knowing. As for telling a neighbor, why would anyone do that. If that neighbor is a best friend that's different but then one usually refers to them as my friend not neighbor. Your sexual preferences in my opinion should not be shared with the neighborhood and that very well might be just what your doing by telling a person you don't really know next door.
Now that I've given my opinion i have a true experience that relates to this subject
My sister lives in the city in a neighborhood with the houses on very small lots . Every one on that cul-de-sac can see every car and occupant if they park and get out. Everyone had seen the various vehicles and even a few walkers who went to one house day after day. The wife home alone all day the husband a 9to5 guy. It didn't take long before seven different men were identified going in and out only there for around two and a half hours each. One or two times a week. Five black males and two who looked Hispanic. Several months went by you can imagine the talk. The case was solved and the gossip killed one Saturday afternoon. The husband washing his new truck, a neighbor walking his dog. He stopped to admire the truck and learned it was only possible to buy because of his wife's new income. Unable to secure a permanent position she was tutoring exchange students sent to her by the UofA. One can only imagine how that may have ruined the day of those sure there was something sinister going on.