Also remember we are not only talking paysites and tubes here. The bigger tubes monetize by dating, cams, dick pills, etc. The smaller 'niche' tubes are trying to monetize their niche so you don't see as many dating, cams and dick pill ads on those sites. Or, if you do see them, the niche crowd ignores them because they are looking for, you know, their niche.
With big tubes it's like Wal-Mart. There are enough diversified interests via millions of visitors that you can monetize in many differant ways. Plus add in the Law of Big Numbers and there ya go.
