I don't even think it's profitable to just post for givaways and stuff.
It could be very profitable. If you're willing to put in the work and have a handful of accounts posting with signature deals you could earn a decent wage. Look at all the coins that get given away in their infancy; if you hold on to them they might be worth something.
hmm... 50 posts with primedice is 0.03 BTC I believe.
0.03 BTC ~ $20
It takes about 1.5 min * 50 = 75 minutes for $20
75 minutes is 1.25 hours which means that posting is about $16 an hour.
That's an OK wage, not too bad but not too much either for just posting