The thing about Shuro is that he left to party to immediatly go ask for help for his retainers (who came to the island with him). He was aware Laios and the rest of the party had no money or food, and that's why he left: to find another party who was better prepared and who could be ready quickly to go back and save Falin. He mentioned this to Namari (who told Laios and co run into her new party in the fourth floor). Shuro had no idea Laios and the others will immediatly go back deciding to eat monsters to make up to their lack of food. Laios and the others speedrun the dungeon until reaching the dragon thanks to Senshi (who told them how to cook and also being friends with orcs), as well as thanks to Chilchuck who knew the shortcuts. The fact that Shuro and his party was only a couple of days behind them is because he forgo eating and sleeping (I guess also because he was anxious and couldn't do either since his group managed to eat/sleep some unlike him). So the Shuro Laios found was hangry and at the end of his rope, so I can't blame him much for exploding of what he perceived the nonchalant way Laios went around things.
