I posted a prompt a while back where Foggy is in touch with his birth mother Rosalind Sharpe, and she sneaks in one night while he's asleep and cuts his hair in an attempt to make him go to the hairdresser for a "proper" haircut. i.e. one that she approves of.

But I could also imagine a bad guy cutting Foggy's hair; for instance, if they kidnapped him and wanted to send a message to Matt, they could shave his head and put the hair in an envelope, then write something like "It'll be his ears next if you don't drop the XYZ case!"