I tend to run them as pretty varied. Less witha dichotomy between good and evil and more with one between uncivilized and civilized. Goblins have weird environmental adaptation going on and are highly mutagenic, so a goblin having all its needs met and surrounded by other civilized people is going to net you your typical 'attractive' goblin. But because poverty andd eprivation can cause them to rapidly become feral as their bodies shift energy from things like thought and social intelligence to brute survival, they can be absolute bastards to avoid this at any cost. Hence the reputation as bankers and thieves.