Are cheat meals... I mean #cheatmeal, just a social media trend for people to take pics of whatever junk food they overindulge in once a week? Or is there some beneficial reason to cheat?

I've been eating extremely clean lately and eating any kind of junk doesn't remotely intrest me but do I need to be that religious? I'm also an mma fighter so I'm not eating high calories to cultivate mass FYI.