0.5BTC? dude, you are either kidding or you have a million referals, 3000$ is not a low ammount.....
NOTE right now site is down any one else have problem its showing site is down for me
I agree with you. No way he's able to earn 0.5 BTC per month from referrals or from any other way regularly. That's a very big amount and I think that indeed he missed a few zeros there.
If he is one of the early adapters or early users of freebitco.in, there is a possibility. Having thousands of referrals (if ever) would make that possible.
Even though early adapter of freebitco site but it is quite hard to find referral who are still active so long because I also got more than 15 referrals but only two to three guys claim a couple of times in a week. I think making 0.5BTC per month is quite challenging from referrals that too now each person claim has reduced because of high BTC prices.