I've often wondered why high-stakes gambling isn't handled more like brokerage. Needing cash to play introduces *at least* the problems you mention: losing it or getting robbed (by other than the cops) are just two others. It would actually be much easier for you to show up to a tournament, sign in, and have your wins and losses tallied, much in the way chips are used now, but checking in and checking out could be done via FedWire rather than pulling out a wad of $100s.
This is not to say that I'm in support of expiring cash or cash tracking per se, but it's not going to put you "out of business" ... the houses wouldn't let you go out of business.
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Unless of course the reason you use cash is that you don't declare all your winnings. In which case complaining about it in a public forum is, let's say, risky.
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The real item behind cash tracking is black market activities.
The trick will be to figrue out a way of keeping the economist view (presented in the referenced article: cash out of circulation is bad for the economy) away from the fascist view of tracking your purchases; its too easy for the economist to be lured into thinking that this is a great way to "solve" their (deeply different) problem.
For now, your best bet is to get as many credit cards as you can, use them randomly, and flood the system with data that can't be auto-corelated. Credit card companies have too much to lose to share that data with each other and fill in the mising pieces of your life, at least for now.
/jordan