How do you deal with an 'on the way out' pet?

Our vet charges by weight...and then the cremation and return of ashes. I don't care what it costs. I love my 5 dogs like they were my kids...and have no problem paying. Maybe I am wrong but when you take in an animal and make them a pet it is your responsibility to take care of it. Part of that responsibility is to see that the pets life ends with some dignity and compassion...something it sounds like some may be lacking. Hell, just go to the closest area that has a serious drop off on the side of the road and just toss it...