Why does no one seem to post those certification pictures? Is there any potential danger or downside to it?

I'm talking about the pictures you take with the sheet of paper stating your username, current date, and ID, like the ones you see prior to logging in. One with a supposedly randomly designated object and one without it. In fact is itreallya random object, or do they just ask everyone to use the same kind of object? The reason why I'm asking this is, I submitted my certification pictures yesterday (in my birthday suit on my birthday!) and just noticed that they were approved on the same day, so I was kind of looking forward to seeing them online... But they were not automatically added to my media. Is it a stupid idea to post them manually? Like can they be used against me in any way that other pictures showing my face can't already, i.e. can they be used to steal my account or revoke my certification status if somebody else submits them after editing the data written on it? Security aside, is it cringe / a faux pas to post those pics like certification is some kind of milestone or trophy?