PvP Betting mechanic for in-game currency

This is an idea I came up with to help people's in-game currency amount later on in the game when higher chrystals, more credits and more energy are required to build up characters...... It's an in-game betting system where you can place a wager of chrystals, energy or credits on your arena matches(there would be a limit per level of course). This could be something that unlocks when you hit some of the highest levels or even just when you hit level 80. It allows for you to basically make chrystals and things back off your PvP matches. There would of course always be the chance you would lose what you invested. To add another mechanic to this, the defending team (the one that is run by the AI) will get the currency that you bet on the match if your team loses.

Thoughts? good idea bad one? more to add?