Trading and gambling is quite different but i have to admit that the risk of them is equal because if trading without knowledges it similar to put the money into gambling which only rely on the luck but if speaking which is profitable i think  it could be various answers but some people can being an good traders and they can earn money from that which mean those people will says trading is more profitable rather than build the casino but for the casino owners certainly running this bussiness is very profitable because they can earn money from the players who playing at their casinos