It may have to do with having twice the angle on your front foot. I have symmetrical forward lean on my bindings, but my bindings angles are symmetrical too.
With your front turned that much farther forward, the actual lean towards your toe edge is probably the same as when you have your back foot backed off a few notches.
I wouldn't worry about it, use the setup that feels most comfortable for you!
edit: I should mention my post assumed your highbacks are still in line with your bindings, instead of turned to be parallel with the heel edge.