gambling managed in a mathematical / smart-way becomes a stable and profitable activity like trading.

only problem, to manage the typical variables of this activity you must have an "hedge". this will affect the profit and deserve a lot of research in some cases. you have two choices, risk a larger amount of money or trying to collect just a small profit.

With term "gambling" I always talk about bets related to sport and not to "casino" games in which it is practically always certain that the house manages to win in the long term...