I caught Milo doing it over the weekend, he doesn't tip them, he puts his paws around them and drags them, he is really strong I don't quite understand why he does it though.
He does it too his food bowl too its never where we've left it. We always put his food down far away from Jess as they don't like to eat near each other, and we always find Milo's bowl in the lounge and his food all over the place.
Over the years we've moved the water bowls all round the house and we've had the same problem so I don't think its a case of trying different areas for the water, the flooring in our bedroom is coming up now as well.