This water bottle thing is an Aprils Fools joke originating in New Zealand. Well over 25 years ago (on Aprils Fools Day remember) two professional gardeners were on the radio giving gardening tips. Whether it was a planned joke or not, they started saying a plastic bottle of water on front lawns will stop dogs pooing there. And LO! - the next day there were a few bottles on lawns. Then, over the next while, many bottles and so on. Then a year or so later the hoax jumped the Tasman Sea to Australia. After that the two gardeners decided to say it was all a joke. I haven't seen a water bottle on a NZ lawn for many years but am incredulous they are around the world.