I agree that begging shouldn't be bannable. You can express your "vote" against begging by simply not giving anything.
To the beggar: I was the same, I wanted a way of testing bitcoin before committing. I did so using the appropriate method though: the bitcoin testnet.
You can run the bitcoin client in testnet mode and I believe the testnet bitcoin faucet still has coins. They aren't worth anything, and they can instantly vanish if some test happens to require it; but you'll get the idea of how it all works.https://testnet.freebitcoins.appspot.com/
Then you take the next step... transfer a few dollars to Mt.Gox (or some other exchange) and buy some. If you are sitting in front of a computer then you can surely afford a few dollars?