And they reveal this information because?????????
Because code names were used back in the day before you could encrypt communications very well, and radios were the primary method of communication. These days, since there are all kinds of security measures you can take to prevent anyone unauthorised from seeing/hearing your communications, and it would be pretty easy to guess who’s who, they’re more for fun and tradition than security purposes. Plus, I’ve also heard that the Secret Service can and will come up with alternate code names for very sensitive situations... which could actually work to their advantage, if the person listening in was listening for the publicly announced code names.