'Free Dog - needs space to run...'
I see this type of ad many times, often describing high energy dogs living in restricted space, driving their owner crazy, I suppose. So they want to do the dog a favor and send it to the country, where it can ran free.
This is about the biggest misconception. Country dogs are definitely not encouraged to "run free". I live in the country and the dogs I know have been trained to understand the boundaries of the property they live on, are outside under supervision, are confined over night and at the owner's absence, whether house-dogs or dog-pen dogs, working dog or pet.
Any dog roaming un-restricted has an irresponsible owner, gets into trouble - often with fatal results.
I did have city visitors bringing their dogs and letting them loose, and when I requested they control them, they thought I was daft.
Someone in the area had a couple of Shar-Peis running loose at night, they dug under the goat-pen (hot-wire kept them from going over the fence) and attacked and nearly killed one of my goats. Later I found out they killed several goats in the area - and they were never heard of again, probably got shot.
It's very rural here, we do not have easy acess to Animal control or the Police, we know we are responible for our dog's behavior and that's ok.
If they run free, they probably get eaten, we have Mt.Lions on patrol. If they bother livestock, they likely get shot, the rancher has the right to do so.