I have spent a couple of hours with that, got around 2 mB and still can't send the first satoshi to anyone because of mining fees (using
http://blockchain.info).
What's the point of free bitcoins websites?
if you are holding a large amount of bitcoin than giving newbies a way to get a toe in the water increases the likelyhood that they will buy a serious amount of btc. If they do this than it increases demand for btc and thus increases the price of btc. So a person who is holding a large amount of btc can actually gain more from giving away btc than they have given away, in nominal terms.
also im sure some people just like to be nice