J.K. says this about the subject (related to the Sword of Gryffindor):
Within the magical world, physical possession is not necessarily a guarantee of ownership. This concept applies to the three Deathly Hallows, and also to Gryffindor's sword.
I am interested in what happens when cultural beliefs collide. In the Harry Potter books, the most militant of the goblin race consider all goblin-made objects to be theirs by right
Of special note is her use of the phrase "most militant" - this implies that goblin culture is not a monoculture and that different sects may have different ideas.
Additionally, given the use of the term 'goblin' here to denote the culture/race, there seems to be no indication that there wouldn't be the common sense ancestral passing down at play in militant goblin society. The distinction then is not just goblin/wizard but militant-goblin / goblin/wizard and how they view objects: rentals or owned.
Additionally, it could be that the sword itself is a special case that initiated this type of thinking and this is what the 'militant' goblins divide themselves over. Some goblins initially considered the sword stolen and this story became a legend that was passed down to the point that it was a cause of the Goblin Rebellions (1)(2)(1)(2):
(1) http://harrypotter.wikia.com/wiki/Ragnuk#cite_note-1
(2) What were the W.O.M.B.A.T questions on Rowling's old site?