Please do try to find the owner! Things happen-- pets get lost-- and it can be very hard to judge the sort of owner by the appearance of the animal, especially when talking about a long haired dog that could become matted and messy really quickly. I know there are some days when people must look at Penny and wonder if I take proper care of her just because she chose to tear through some long grass or a sticker bush ten minutes earlier and we haven't made it back to the car to brush her out yet.
A few years back, when I was working at an animal hospital in SW Michigan, we had a lady bring in a very skinny cat that had been hanging out in the alley behind the restaurant that she owned. She planned to keep him, but she wanted him scanned for a microchip first just in case. Now, if there was ever a pet that we DIDN'T think we would find a chip in, it was this cat-- he looked so pitiful and thin-- but sure enough he had a chip. We called it in, and found that he had disappeared almost a YEAR earlier 300 miles and 3 states away! The owner was shocked and completely overjoyed-- I offered to hold on to the cat for him and care for him at the hospital until the weekend, but instead the owner immediately left work and drove 300 miles at god only knows what speed so that he could pick up his kitty that same day. His family had been sure that they would never see the cat again, since he was a pampered housecat that had never even set a foot outside their house until the day he vanished-- but somehow he wound up 300 miles from home, and survived a Midwestern winter and god only knows what other hardships. And he had a very good owner waiting for him!