Not to rain on anyone's parade (yes, I have liberated planting containers from curbside), but if someone came to my door making statements about having seen stuff on my private property which they would like...I would be completely freaked out.
your "private property"??? I'm not talking about walking around the back of their houses, or climbing on their porches, or sneaking around their fences. I'm talking about people who have super visible front porches with 20 flower pots on the ledge, 1 of which has any plants in it. or people with a dozen 20 gallon planters that you've seen remain unplanted for 3 growing seasons.
We were broken into more than once while we lived in Berkeley, one time when we were gone only for 45 minutes. We were being watched, clearly. There was even a SWAT team raid once at the apartment bldg. on our immediate south (common property line) for cocaine dealing. We had found crack pipes in our bamboo shortly before the SWAT team raid.
oh. well, if i lived in a neighborhood such as the one you apparently live in, i would not recommend even talking to your neighbors, much less mentioning their empty flower pots.
So anyone who comes to my door--even after we've lived in this nice, quiet neighborhood for several years--will get the full "private property; you have no right examining anything I may have here" speech.
oh, it's a good neighborhood? weird. then you are just jaded? i've been broken into twice. once, i came home while the guy was in the house rummaging through my guns. he was a homeless guy who i had paid to cut my grass a few times out of kindness, knowing he was at least trying to do work for money... my sister (who is in the army and was staying with me while on leave) was in the house asleep. he had knocked her dog out with a wine bottle. i chased him through the alleys, to no avail. the other time, i came home to a ransacked house, missing a bunch of electronics.
but, if a neighbor comes to my door and makes mention of something on my front lawn that I'm obviously not using, I'm going to either say, "nah, I'm going to use that", or "Sure!"
I'm sorry that you are jaded and emotionally scarred from your experiences. I'm even more sorry that this makes you distance yourself from your neighbors and community members. but, it's not going to stop me from being a nice friendly neighbor, always willing to give away an egg or two, or a cup of sugar, or a flower pot i haven't used in years....
To anyone thinking of this approach--please consider what may have happened previously to people whose doors you approach, and be prepared to receive an emotional onslaught if their experience was similar to mine.
how terribly saddening. if you onslaughted me, i'd take the time to try to explain that no amount of walling yourself in a house you consider "private property" will keep you safe, and that the only way to really affect the world is to be kind and caring. bad things happen to good people sometimes. what's terrible is when that turns good people into scared and scarred people who are afraid of neighbors asking for their unused flower pots on their lawn....
anything in public view on your property, anyone, and everyone, has the right to examine. your privacy is only protected in private places.