I think you've got the wrong expo man. I take it you have never been to the FIA. I also take it you have no interest in foreign markets. I would say at least half of the vendors there are foreign exchanges and brokers. If you ever wanted to learn about Asian, European, Middle Eastern or South American markets, there is not a better place to go. You will learn about emerging markets, new trading products being developed as well as how to gain access to foreign derivatives. I guess if you are just a stock daytrader, stick to what you are doing. But for some who actually want to grow a little and gain some exposure to things outside the US, it's an invaluable experience. I guess to each their own.
Any idea of cost? I've been there before and agree it's worth going to, but I usually got in through another trader.