It's always an eye opener to look up companies at http://www.h1bwage.com/ and compare their salaries. Plenty of SF companies hire 'senior software engineers' in the range of 78K.
I looked up companies that I once worked for on h1bwage and I know for a fact that my H1B co-workers were not enjoying large bonuses.
A visa application listing a bay area senior s/w engineer prevailing wage of 78K should be outright rejected. Yet, it was accepted.