Lisa you have to understand that these dogs go through specialized training, in addition to obedience training, add in the cost of vet care, required shots, license, food, it adds up in a hurry.
The dogs are also housed with their trainer, who is compensated for housing the dogs, as well as training the dogs to recognize the different medical issues, such as oncoming seizures, etc.
Currently, the Veteran's Administration has put a hold on covering the cost of service dogs for veterans, who suffer from PTSD, as the VA feels more research is needed to determine whether the cost is justified, as well as whether the service these dogs provide is beneficial or needed.
There was a time when service dogs were known only as guide dogs who assisted the blind. Probably within the past 20 years or so, dogs have taken on more specialized training to assist people with other medical or physical issues. As such, the expense for training the dogs for these specialized needs has increased considerably.
Here is the News10NBC link about the VA story I was referring to before:



Is this the same little girl who was promised a dog quite some time again and the deal fell through? I thought she got another pup. I supposed the dog passed or didn't work out. Wow, what a cost. A shame it's not less expensive or covered under some grant or something.