De gör.
Som anges av J.K. Rowling på Pottermore :
The International Statute of Secrecy laid down clear guidelines on dress for witches and wizards when they are out in public.
When mingling with Muggles, wizards and witches will adopt an entirely Muggle standard of dress, which will conform as closely as possible to the fashion of the day. Clothing must be appropriate to the climate, the geographical region and the occasion. Nothing self-altering or adjusting is to be worn in front of Muggles.
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Day to day, however, even those who detest Muggles wear a version of Muggle clothing, which is undeniably practical compared with robes. Anti-Muggles will often attempt to demonstrate their superiority by adopting a deliberately flamboyant, out-of-date or dandyish style in public.
Vi kan antyda att de flesta trollkarlar regelbundet bär Muggle kläder. Om även de som avskyr Muggles fortfarande bär Muggle eller Muggle-liknande kläder helt enkelt av bekvämlighet och / eller praktiska, så är det säkert de som inte har något emot Muggles eller är välkomna av dem, gör detsamma.