Most of the new people loss their money in the gambling just to learn the game,the new gamblers should play the demo game as the initial phase.With my knowledge seventy percentage of the gamblers only play the game with the real money from the beginning of the gambling,the reason began this was they will get inspired by the person close to them and made the big winning in gambling..
Have you read or heard about newbie gambler's who come into the gambling scene and making a bet for the first to get a huge win that even long time gamblers have never had. When you hear stories like this, why would you want to spend time on demo instead of going straight up with the real events with real money. After all, gambling is mainly about luck.
However, there are games that as a newbie it would require you go with demo for a start to understand the procedures and rules of play, like slot games but for sports betting I don't see a need to start off with demo. Just pray you're in luck while making your predictions.