Why not?

To the extent that profit sharing is based on a percentage of our wages, it becomes a variable component of those wages. So, if Airline A pays $100/hour with a profit sharing plan that can pay up to 20% and Airline B pays $100/hour with no profit sharing plan, one can correctly state that Airline A pays its pilots a variable rate of $100-120/hour and therefore more on average than Airline B (assuming an average profitability > 0).