You misunderstood. No profit does not equal loss.

The employee builds a Steam Machine with either a €100 or €250 drive. All costs are the same except for that drive. However, the difference in price the end consumer pays is not a €150 difference but a €320 one.

This implies Valve takes their costs and just adds a percentage margin over it for profit. And I'm saying they shouldn't do that. Pay what must be paid and let us pay the same.