I'm going to start cleaning house, too because I have too many neighbours. I have 94 and I think about 15 are decent ones. I'm not going to penalize newbies because they might not know any better, but it really annoys me when someone with a level 50 or so gifts me french toast and instantly requests a current part. I've even updated my wall and only requested parts, but I know not everyone has time to read wall posts.
I have more than enough food and clearly don't need more, even if it's stew. The only time I send food is when I know the person is very new and has very little food - no need sending parts they can't use at that time.
I know this is just a game, but it can be annoying when you're a good nbr and have to deal with selfish ones.