Boy...hahahaha, thats a mouthful. Every individual right you have crumbling under the weight of one sentence. I hear that the Jews and communists who were caught by the Nazis for starting the Reichstag fire back in the '30s were "caught red handed". No doubt the beatings administered were justice too. Want more? History is filled with them.
You see this is how it begins. It all starts with everybody meaning well and feeling all righteous. It begins with the exceptions made.
And no Anodizer. 9/10'th of the time we wont tell the shop owner what to say. Thats against the law too and why would we risk our jobs to protect some nitwit who decided his need for payback was more important then being lawful?
Yeah I just watched the entire thing. The last two kicks, after the store guy took off his jacket and before he dragged the offender out of the camera view?? These kicks were purely unlawful and couldnt be justified. This store owner would have bee arrested as well.
Then you are the other tenth that wouldn't give the good guy a little help to stay out of trouble for doing the right thing... I know lots of cops that welcome this sort of thing.. Makes their jobs easier...
Chances are this kid will do/did 6 months, max... Or he may be sentenced to a year and get out after 30 days on a judicial order and placed on probation.. The only thing the justice system is worried about is money.. The kid gets a D.O.C. number.. The dept. of corrections gets its money.. And violla, joey douchbag thug wanna be gets out early... With jail/prison over crowding, this stuff is not a priority for the actual justice system.. Maybe it is for you cops, but when it gets down to it, this stuff is petty.. Basically, when the system gets a hold of him, he'll do little time and go out and do the same thing after he finds out he's a looser and will never have a viable life or a viable job.. He'll try to rob/shoplift/steal again... But he won't do it at this guy's store.....

One last thing.. "Lawful" is a broad term... The "Law" is pliable like silly puddy... People who execute the "law" have discretion.... Just like the good cops who'd see this for what it was
and wouldn't purposefully try to get the shop employee/owner in trouble...
It sounds like you'd be the kind of cop that would... Shame on you...