Probably depends on your area, but I do routinely see "trained" LGDs come through the shelter and rescue system every so often (obviously you'll want to know why they ended up there). We almost adopted a male that failed due to chasing large animals, but was otherwise used to living outside and working. We currently have an Anatolian that was raised as a pet, so she lives indoors, but yes she's very barky which is why she got turned in to the shelter - as we live on a private lot there's very little to trigger her at home so the barking isn't an issue for us.