As a vet tech, I almost always advise removal of back dewclaws. It can be very dangerous to leave them on, not to mention extremely painful for the dog, and more expensive to the owner if and when they cause problems. Especially "unattached" dewclaws.
Of course it is best to have it done along with another surgery, so they only have to go under anesthesia once, but it's definately advised either way. A lot of times you hear the excuse about the dog not experiencing any problems. It isn't until the problems occur when the owners finally get a rude awakening(not to mention the animals).
We've done a good bit of declaw removals, and it's definately for the better, and would not be considered cosmetic surgery. It's defiantely necessary and crucial to the well being of the animal.
They serve no real purpose, especially in today's world.
Recovery is usually very well received, and now that there is approved post op pain meds, that makes most people feel better. I have yet to see a case where there were complications from the dewclaw removals. The animals are able to walk out of the hospital jsut fine that night, and are able to get up and walk hours after the surgery.
So, no it's definately not even remotely close to being inhumane.