He was the one that could have given the ticket and walked away with it unsigned.
It would be tough to issue a ticket and not have it stand in court with her DL info and a tag # plus video confirmation.
I never sign a credit card receipt. Usually draw a happy face on it and it comes back as as signature accepted.
A lot of businesses don’t require signatures now at all.
A signature is much different than a mark. All that is required for a signing a legal document is your mark, which most people use their signature. A bit of history: When native americans were signing legal documents back in the 17-1800's many didn't speak english nor wrote it, so they put their mark, usually some symbol or just an x (this is where the x on some signature lines come from). All that is required for a legal document is your mark, whatever you chose. This is why when you sign a CC receipt with something other than your signature its accepted unless stated they need a signature.
Signing the ticket, as stated before, is needed to be released on the promissory that you will either show up for court or pay the ticket. Yes, there are a few that are doing e-tickets, but not many and most jurisdictions still require a signature. If he let her have the ticket without signing she can go to court and say she never got the ticket and it would be dropped.