What happens if you go inside a store in the middle of the night and eat all of the candy in there?

You are tased repeatedly by the owner when he comes back in to open the store. Good luck with that. 

You get arrested by the police.

You might get arrested. Possibly kicked out for a long time.

How are you going to get into a store in the middle of the night without alerting the police? You aren't going to get very far.

A secret retail managers don't want you to know is prosecution often costs more than what the average punk-*** can steal. Meaning, you can stuff a bag full of merch and you'll just be kicked out and not even have to give back the stuff because they know at the very least, it'll take them a whole day to go to court against you. That's time they could be getting paid $400 plus they'll have to cover the man hours by paying 3 schmucks overtime worth another $300. All for $8 worth of Slim Jims you pocketed at the dollar store.

I'm not encouraging it. That's a really shitty thing to do  but the fact is what will happen is usually not much. That said, you will be recognized by security and lose access to a resource in your community. You now have no option but to pay $17 for a gallon of Tide Ultra organic at the fancy store because you've been kicked out of every other place that offers no name detergent at $1 for a lb and a half.

For $8 worth of snacks you now pay $3000 more over 7 years because you got banned from the dollar store. Those numbers don't work in your favor by my calculations.

You would be very sick, then you'd be arrested!

Kicked out. Arrested. Do that in my area you'll prob get kidnapped.