I think this seems like a good idea.
No support for the suggestion of interest though. Since C$ originates from real money, this would benefit those who earn C$ through trades, etc. more, in that I don't have to spend a cent of real money and I'd get it saved up. Also building on someone's point, the money goes to support the site and keep it running.
Another thing I haven't seen anyone bring up (unless I missed it, then my bad), but could be useful, is perhaps a feature in the bank to limit withdrawal? So you can deposit unlimited amount of times to your bank, but maybe only withdraw "x amount of times" per week or per month. And "x" can be a set number globally for all users, so individuals don't have too much control otherwise this feature would lose it's purpose. For those who really need extra help on impulse control. (Now, if you go ahead and withdraw all of it....can't do much for you there

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