I think your nephew's attitude says a lot about how he is being raised.
I grew up in a house with pets who got mediocre (sp) care. Our dogs got puppy shots, rabies shot once and were licensed thats about it. They had food and water and love but I never felt it was enough.
Now that I am an adult caring for a kitten as well as three water turtles I understand how they deserve more than what my parents provided to my pets as a child. My new kitten eats a very good quality food, has been neutered already, has been treated for both fleas, an eye infection, a upper respitory infection and a yeast infection in his ear (his time on the street caused these things). And although my turtles have never seen a vet, I have a number ready for a herp vet if they were to need a visit.
What is funny is my husband grew up in a house with similar attitudes for pets--actually worse than my house. No animals were in the house and his parents have a hunting dog that hasn't left his 6'x6' pen in over two years because my fil hasn't gone hunting (she got to leave over christmas for the first time in 2 years--my husband took her out and ran her through the woods).
He agrees with my attitude and wants our kids to know better.