Why is it called Boston Cream Pie, not Boston Cream Cake? ?

Come on, it really is cake. Why is it called Boston Cream Pie, not Boston Cream Cake? ?
It is really a cake.





Colonists to the Boston area originally baked thier cakes in pie tins. This cake, when first made in Boston was also baked in a pie tin... hence the name. Why is it called Boston Cream Pie, not Boston Cream Cake? ?
it was baked in a pie tin and was also george Washington's favorite dessert.
I guess they didn't know the difference.
Very good point you make. Never thought of that before, hum!