Goblins are survivalists (generally, though there are exceptions). Things like morality, pride, honour, all these take a back seat to the survival of the tribe, it's why Goblins are far more likely to take an opportunity to flee and save themselves, than they are to make a stand against overwhelming odds. It's also why they might eat what meat is available, even if that meat was their friend two minutes ago. The ends justify the means when it comes to living another day.