A system comprising a consumer good, especially a packet of cigarettes or packet of pharmaceutical products, and a server has a consumer good fitted with a concealed code, wherein the code is associated with an advantage having a monetary value and can be transmitted to a server via a telecommunication link, the server being used to check whether the code is registered as valid, and depending on the result of this test, an advantage with a monetary value is credited by the server to the telecommunication number of the caller.