"Why would you want Bitcoins instead of cash?". For a second I didn't know what to say; then I thought about it and here is what I came up with. Feel free to contribute to this.
1) More security (especially if you are careful).
2) Bitcoins are a potential investment, cash is not. Paper currency only really goes down in value, Bitcoins have a lot of potential to be worth more as time goes on.
3) Fast, worldwide transactions at your fingertips.
4) Similar to #3, but it's a universal currency. It's legal in most countries of the world and you don't need any kind of currency conversion to send money to people in a different country than your own.
i agree that it's really fast and easy to pay with, and small fees, and it is pretty safe too, while you can get more money from it if you keep your coints for while, but i can't agree with legal/illegal price, in lots of countries it's not legal sadly, and it will take years to be legal everywhere
Even if it is illegal people will continue t use it as no one can have control over it and no one would be aware what amount of bitcoins you hold in your digital wallet and that makes if more attractive then normal currency.
If governments would like to forbid cryptocurrencies then using it might be hard without some proxies like tor. Besides missing acceptance merchants the government could force the ISP's to look out for certain ports and connections that lead to the assumption someone is using bitcoin.
At that point it might be needed to use things that were developed by filesharing software devs. Things like dynamic port change, encrypted traffic and such. I think emule, and especially the mods, had alot of ways to stay hidden.
Well of course it can't help against agents taking part in the network and finding your IP. For that only proxies and such are helping.