Give an advantages of using shock collars?

I suspect the answer you get will depend upon the political orientation of the one posting the answer.

Would you be so kind as to clarify this question? Do  you mean the shock collars used to discourage barking, the shock collars associated with an electric/invisible fence, or something else.

One advantage is that you can train the dog from a distance. If you let your dog into the back yard and he immediately chases the neighbor's cat, you can teach him not to do that without actually chasing after him yourself.

someone is sure to say that these collars are cruel, but dogs learn very fast. It's not as if you are torturing him all day. One or two good zaps and he'll get the message.

I remember when we had an invisible fence. Tyler the Crazy went nuts and bolted across it to chase something. What or who ever it was escaped. We had to bodily carry him back into the yard. He got real squirmy when when approached the shock zone.

I am a 69yr. old woman who is able to whistle various sounds various pitches . My 2 dogs are both trained to come to me when out in the yard, stay in the house,i will be back soon, stopbarking (I learned this from watching a Scottish  Sheep herder work with his  sheep dogs. on TV. )No need to hell ,hit, scream, shock, cry,  it is a peaceful environment here and they seem  very contented.One is 16 years old  he is a mutt i found on the street and one is a 6 yr old  formerly  abused  goldne retreiver.  we are a  happy  family.Never do to your dogs anything you wouldn't do  to yourself.