Legendary

is the kindness of Stamboulians to street dogs.

There is a reason.  The Prophet's sole statement about dogs
is that they should be treated with kindness,
should not be kept in the home merely as pets,
but only as working dogs:
guarding (Surat Al-Kahf, Quran18:17-18),
hunting (Surat Al-Ma’idah  Quran 5:4),
and by extension herding, guiding, sniffing, diagnosing etc.  

No animal is of itself haram, but it is haram (as it is trefah) to eat pork.

Meat brought in the mouth of a dog may be eaten,
and indeed, in times of want, dog itself might be eaten,
if it is not infected or road-kill.

Thus the wily, dog-loving Turks adopt street-dogs as pets.

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A few Hadith refer to dogs – for example :

According to Abu Hurairah (May Allah be pleased with him), 
The Messenger of The Lord God (Peace be upon him) told the story
of a man who, after walking a long way, became extremely thirsty. Having, by God's grace, discovered a well, he climbed down into it to drink.

On leaving it, he saw, close by, a dog who was eating moist earth out of extreme thirst. The man said to himself: ‘This dog is as thirsty as I was.’ So he climbed back into the well, took off one of his boots and filled it with the cool water. Holding it in his teeth, he climbed back up and offered it to the dog. The Lord God appreciated his action and forgave his sins”.

The Companions asked: “Shall we be rewarded for showing kindness to the animals also?” He (May the Blessings of God be upon him) said, “Kindness to every creature of God's creation will be rewarded hereafter.” 

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Curiously, according to another hadith, Angels of Islam will not enter a house in which there is a statue, a painting, a photograph, any 'graven image', or a dog.

Dogs are neither haram nor worthless:
unlike humans, they are themselves.