Mozilla Foundation has a staff of 80 and "manages" about 1000 volunteers. It's unclear how much donations it gets as they published a consolidated report that includes the corporation. I expect that very little.
Mozilla Corporation has a staff of 750 and $400M revenue (I expect most from the Google search deal).
No, the problem is that people don't understand what non-profit means. It has nothing to do with the internal structure of the company, employee salary (CEO is also an employee) etc. It has to do with external structure, i.e. ownership and distribution of profits (which there cannot be any).
Mozilla CEO's salary isn't even that big, in the large scheme of things.
The fact that one of the subsidiaries is structured as a for-profit is a red herring. Just a legal structure. The whole organisation is non-profit.