Definitely and I'm quite sure any social individual must have gone through similar experience. Gambling isn't just a sport thing per se. It's a part of our life as humans, without thinking much you would easily recall some childhood memories that involved you gambling irrespective of money been involved sometimes just to prove you were right or for the boosting right (ego).

Placing a bet with your siblings could also be considered as gambling irrespective of no monetary value coming into the discussion. Since there's something on the line which will result to one party lossing while the other benefiting, it can still be considered as gamby.