No, because as far as I know there are no certain taxation laws that are covering the people who are working here on forum and there is no law also here in forum that you need to pay tax once you got some big bucks done.
That is why, many people from cyber world are becoming richer than people who works in real life, because they don't pay tax.
indeed. these services are not covered by taxes so that's why most freelancers or businesses uses this type of forum so that they can get away with taxes or fees. this is actually one of the advantages in the world of bitcoin.