It's another issue of people not using something properly - TIE-OUTS. I support anti-tethering laws and routinely question people about their tie-out habits because there is so a thing as too much, BUT I regularly use a tie-out with Bourbon and Baron.
Our tie-out is mainly utilized for potty breaks (because Bourbon can't walk down the street without screaming his fool head off at birds, squirrels, rabbits, neighborhood dogs, etc. the whole way) and as a way to keep them contained in a specific area if we are outside doing something.
Like when we don't want Baron in the pond (which happens any time he is free in the backyard)...
...we give him a small baby pool on the tie-out to enjoy instead. I know, I know, not quite the same :)
Bourbon's favorite time to be on it is over my lunch hour. I go home for lunch almost every day so the dogs have a nice break and can have a chance to potty. Bourbon likes to utilize this time on the tie-out sunbathing.
Any time the dogs are on the tie-out I am still keeping an eye on them, either through the kitchen window or outside with them. They are never on the tie-out unattended and never for more than an hour (which only applies in Bourbon's case as Baron only likes to be on it for no more than 15 or so minutes, while Bourbon would spend hours on it).
Dogs that are left on tie-outs for the majority of their days 'accidentally' learn several annoying behaviors. These dogs watch the world pass by and never get a chance to interact with it, which produces a lot of stimulation frustration. Dogs express this by becoming extremely excited at sights and sounds, frenzied barking, and aggressive behavior (biting at a person holding him or biting/snapping at the thing/person that's making him excited). They are left in situations with little to no mental stimulation other than what they can see or hear or smell from the tie-out, which allows for overexcitement when confronted with other stimulus.
Another thing to consider - restraint itself produces excitement. Police dog handlers and protection dog trainers always use restraint techniques (hold the dog back from someone/something 'teasing' the dog) to increase drive and excitement to get the dog to bite better and harder. The restraint itself heightens any excited reaction the dog is going to have.
Tie-out's do have their uses, as long as they are not abused - we are back again to COMMON SENSE. A dog should be safely tethered in a situation where he has NO access to anything he could become entangled with, and be on line strong enough for his body weight. We have ours wrapped around a tree about 6 feet or so up the trunk. Your dog should also be supervised as well :).