stealing

I think he should do something about making the store more secure because this stealing incidents definitely is not good for business. I'm sure your store-owner friend realizes that this occurences decreases his revenue. I'll suggest that he either improve the security features of the store, change location, or hire a security guard. As I said, these stealing is not good for business.

Is your friend normal?Or why do not he fight?

I think its hard to just close a shop just because someone is stealing from it...I mean, he could do something about it like place some security camera or something.

You know what, as a friend, all you could do is to advise him on the stuff but you can never force him to do something about it. It's his store and if ever it will be bankrupt, it will be his problem. I don't think your friend really has a care with the business, and I'm even wondering if he really owns the store or if he has put some capital in it, or it's just him that is asked by the real owner to watch it. Just do your share and whenever you see someone attempting to steal something, why not just call the attention hehehe.. Further, perhaps the things being stolen are just petty and he has put huge profits from the other more-salable items that's why he doesn't worry about those things.

Advice your friend to hire a security officers and put some video camera around the corners of his store. This camera will serve as the proof where the thief was caught in the act of stealing an item. The security officer can also use the camera to monitor multiple corners of the store allowing him to act immediately before the culprit manages to escape.