1) If he is buying physical games--e.g. cartridges, CDs--and then reselling those physically, he is allowed to do so. Of course, he has to worry about paying taxes (collecting sales; paying income) on his transactions, and if he does a sufficient volume, he'll need to in some fashion register or incorporate as dong business; but as a general proposition, if you buy a physical copy of something and resell that one copy, you can do this.2) One caveat to the above; if the terms of purchase/user license/etc. when he buys the games says that he cannot resell them (e.g. only for own use, not commercial use or resale), then he would, at a minimum, be committing a contractual violation when reselling, one he could, in theory, be sued over.3) If he is copying games (e.g. copying software) and selling multiple copies of software, then he is most likely violating intellectual property and potentially subject to stiff penalties. 4) Also, if he makes any declaration, e.g. customs declarations, connected with the  purchase and importation, then he might be violating the law if his actions are not covered the declarations.