Lost pet blues

We have lost our sweet dog for 2 weeks now and our home has a cloud of grief-like quiet around it. We actually took in the dog from someone else who he got away from. They ended up telling us to keep him because they were never home and it sounded like we were giving him a better home than they were. Nice words - and very unselfish of them I thought. We have had him for about 10 months now. He was very energetic and ornery, but there was something about how sweet and lovable he was that made you forgive him right away for everything he destroyed. We were working very hard on housebreaking him and we were having a great deal of success. But he pulled off his cable, broke the ID loop and is now missing with just a collar on. We put ads in every local paper, fliers to every neighbor, posters at every stop sign, and contacted vets and shelters in the area. I know I should have had him micro chipped and if we are blessed enough to get him back , I will do it. However, it seems this time that would not have mattered because whoever has him - is intending to keep him. We had several neighbors say they saw him and then he just was gone in less than an hour. No one has responded to my ads, no one has called or delivered him to a shelter. It seems bleaker and bleaker every day. I thought about this person, if I am right in my assumption, dealing with the reality they have a stolen dog from another family. I, personally, could not do that. The faces of the rightful owners would haunt my thoughts - no matter how great the animal was or how righteous I felt in taking him in. I guess in all of us there is this feeling that we can do better than someone else. The reality is you don't know a person's circumstance unless you lived it. This is a lesson that I need to learn too because I will admit that sometimes I get very frustrated with the lifestyles of people I know when the answer seems so simple to me. Is there an innate nature in us to be uncaring ? Do we look down on people that are doing things just differently than we are whether it be due to ignorance or just their own thoughts that they do it better?