I think it does helped for them to be hand raised. I got my boy Schroeder (who has since passed on
) from a guy who held them often...he wasn't a breeder, it was actually a really bad situation for the chins...BUT, because Schroeder was used to being handled, when I first stuck my hand in his cage to say hello, he climbed right on my hand! He just allowed me to lift him out with no problems! It won me over instantly! Schroeder and I bonded quickly and easily. He was eager to spend time with me! (Probably grateful I saved him from that guy!)
My current chins... a 5 yr old male I have had since last June, was raised by a good family, but handled only occasionally. He doesn't like to be pestered...he'll let me scratch his chin on occasion, but usually I use his bath house to coax him in & out of his cage.
....And now my 7 month old female I just got last month...was from a pet store, but a GOOD local one. She was played with frequently by the guy taking care of her. She usually allows me to pick her up without much fuss. She doesn't walk right onto my hand, but she does stand still while I reach for her.
So...in my experience, it seems that chins that were handled often from early on, are much better about being handled, and very easy to bond with!
BTW - I also HATE seeing how the chins at Petco & Petsmart are treated. They live in glass aquariums full of plastic toys. So sad. It worried me to purchase from there because the chins could be in such bad health after that sort of treatment.