Like others said, it has it's place. If you live in a tight knit community it is useful as people here post heads ups about anything out of the ordinary, when they have some garden items to trade, found pets, etc. The moderators are heavy handed on some things. Negative comments, even those helpful and not offense are deleted but religious posts flourish. We've gotten rid of many excess items and it's not crazy like craigslist.

Minutes from monthly police meetings are posted as well. For me it's the least obtrusive of social sites. As posted above you can invite neighbors to join and most certainly that's what happened in your case.