Merlin took his mask, throwing it in his inventory before leaving, he made sure his hood was at least partially obscuring his face as he shopped. The mask seller would be able to identify any crimes caused by him using the mask and potentially the robe, but Merlin could always hide and change those, but he couldn't change his face.
'Well, if I'm going to be out there, I might as well pick a couple quests to give me an excuse to be out there, and earn some money on the side.' Merlin thought to himself. 'But at the same time they deal in news and rumours, so if the victims start talking about their saviour, some identifiable features might pop up...'
'It's better to be safe than sorry, lets do this.' Merlin took off his warm panther cloak, throwing it back into his inventory before grabbing his apprentice's black cloak and wearing that instead.