How weird, sam4321, he makes up a reason (that doesn’t make sense) and uses that as if it is the reason, enough to say that it doesn’t apply anymore! It’s nice to find reasons, but to be that proud of your reason is silly.
I say that it doesn’t make sense, since the ends that touch are no less baked than the dough in middle of the bread, which is thicker, and therefore further from the heat.
Here’s another reason: The Mishna says that you have to leave Peya for the Shamash. Another one: I heard in the name of the Yaaros D’vash that the end represents the ‘outsiders’. And another yet: Since Chazal tell us that wheat gives Chochma we don’t want the fringes of Chochma.