I thought the same thing but..... I'm not so sure.
Over time Bickerton changed the hinge name from Gen 1 to Gen 2 and aside from changing the inner hinge structure, the appearance/shape remains the same.
While for Gen 1 you need two partially threaded pins (the top and the bottom), in Gen 2 only one solid pin goes across the entire hinge.
They claim it doesn't seem to be failing like Gen 1 did.
So yes, I would think the pins indeed protect the frame in Gen 1, but if Bickerton purposely changed these two bolts into one, maintaining the hinge and frame shape, I'm pretty sure it's not about protection but the method of transferring loads in the hinge.
And what's crucial here - the cylindrical part of the pin is the most loaded part while the pin breaks where the threaded part meets the cylindrical section..So that's a design flaw to my taste.

(for some reason I can't upload any attachment/jpeg. tried many times, it stucks on 90%, anyone knows why?)