"No," said Lizzie: "No, no, no; Their offers should not charm us, Their evil gifts would harm us." (64-66)
Lizzie seems to realize that the goblins' fruits are a temptation to be avoided. Her repeated refusal, "No, no, no," suggests that she does, however, feel the temptation. We get the sense that all maidens who encounter the fruit are tempted.
She thrust a dimpled finger In each ear, shut eyes and ran (67-68)
Seeing and hearing the goblin men could make Lizzie give in to temptation, so she shuts her eyes and ears and runs away. She doesn't trust herself, so she removes herself from the tempting situation. Running with her eyes shut doesn't seem like the best idea, but her intentions are good.
"To take were to purloin" (117)
Laura is about to commit a sin by eating the goblin fruit, but she hasn't thrown all of her scruples to the wind. She doesn't want to "purloin," or steal the fruit, she wants to buy it fair and square. This tells us that she has a moral compass intact.