Is it illegal to drive someone else vehicle even if we have license

Today I was caught by cops for riding a bike on the wrong side of the road, albeit it's a very short distance of 20 meters just crossing a street. I agree it's still an offence. But of the many offences that the police officer made me count, one which intrigued me was that I can't ride some else bike / car if its not under my name. I am valid license holder. I haven't come across this situation before and yes, I was fined heavily for it and given a receipt too. Is it illegal to ride someone's vehicle even though you have a valid license?