The legality of bitcoin is what would matter first and this is jurisdictional based. If it has been legalized where you are then you can do what you like with bitcoin though within the confines of the law as it is enshrined, otherwise, you can't practice such sell.
The thing here is he just need to register his local shop as a business entity and there's nothing wrong with it, that's the due process for someone that wants to start his own business. And he has to declare that he will include selling bitcoins for cash.
Most of the government agencies aren't interested on business matters as long as it is legal and you will be taxed.