Nintendo and Microsoft/Xbox have low margin on each device sold [1] [2].
For Valve, Steam is the only real source of income.
Apple on the other hand has a lot of source of incomes.
They have a margin of 60 percent just for the iPhone! [3]
You have a job and an apartment you lease out. You made a great deal on the apartment. Now, your tenant suggests he should pay less, since you have another income and you already make a profit. Do you?
I don't understand your point - if Nintendo or Sony could achieve larger margins, they would.