Do I really have to say it again?
You keep missing the point, and your arguments boild down to, it won't work.
Guess what, I know you're wrong, most people here know you're wrong. How do I know, if a bullet hits me because I'm trying to walk into a store to loot, I'll stop, if I try again, and I get shot, I'll stop.
Seriously, what on earth can you say to counter that, nothing. When people hit you, it hurts, its that simple. Risk vs reward, right now reward is free stuff and risk is, having to outrun people in heavy equipment who are having very little success. If people start shooting people entering and exiting stores that have been broken into, errm, suddenly the risk is very much more real. What are you going to provoke them into doing, attacking the police or going home, either work for me. Right now they are just running from the police making it hard to grab the *****, if they run at the police, we'll grab them up, stick them in a van and take them elsewhere.
What is the downside, you can't walk into a store and steal stuff, if a high pressure hose is knocking people away from the store, again, get bored, attack the police, something you've not mentioned is being inside a water cannon truck is a HECK of a lot safer than going hand to hand with a group of thugs, maybe they'll run off and try a shop down the road. Truck follows, blasts them again.
In what way won't they help, except, with you saying "but it won't" because most of the arguments I've seen involve you claiming it will do nothing.
Did you ever do anything wrong as a kid, did your parents ever slap your hand if you tried to take something or did something wrong, did you still keep doing it.
Generally pain is a very good way to teach people not to do things, don't touch the hot pain, kid touches it, kid never does it again. Person walks into store to loot, person gets shot, it hurts like crap, he decides, maybe not and goes home, thats a win.