I want to argue back against this one.
I'm coaching my son's 9U tackle team, and we run the unbalanced Single Wing. We go on the same snap count every down - "Everybody Ready! .... Down! ... SetGo." We never change it up.
But literally the very first play we learned this season - in the first 10 minutes of the first practice - is "No play." We come out, we get in our stance, "Everybody Ready! ... Down! ... SetGo!" and everyone stays right in their stance. It's been good for a free five yards almost every single time we run it (We've false started on it twice, and we have an audible for the one or two times the other team hasn't jumped).
It's silly, but it's really important for us. When you go on the same count all the time, at some point the defense is going to figure it out and start jumping our count. Then we run "No Play" a few times (the worst was the time we ran it successfully three straight plays

) and the defense gets off that. Most importantly: Watching our video, after we've "No Played" a few times, our offensive line starts getting a big edge on the defensive line - the bad guys are still in their stance trying to figure out if the ball actually moved this time.
If kids are allowed to "get back" after jumping offsides but not making contact, there becomes little disincentive to trying to jump the snap count, especially for defenders outside of the free blocking area, where they're not going to bump into anyone. Ceding a one-step head start to edge rushers/contain men is a massive, massive advantage.