Geniasis said:
He explains at the end. He wanted to tell someone--not necessarily her, but anyone--his story before he died. Remember this a lonely dude completely cut off from society, companionship, any kind of warmth from another person. But this way he gets to leave behind some proof that he existed at all.
Maybe I neglected to give that part some consideration or skipped over it completely. If that's the case, then I suppose it's a very valid reason for egg dude to tell his backstory.
HOWEVER, the (now-deceased, rip) author could've made that segment a spin-off one-shot or side story or something -- instead of taking a whole chapter just to hone in on some side character!
Assuming there were a lot of unsatisfied people: the author put in something irrelevant and time-consuming at the expense of the audience. (I'm sure there were people who liked the story too, and didn't have any complaints -- but me personally, I don't think it was a necessary addition to the overall story, and should've been scrapped.)
I still think it wasn't the best chapter in the context of the rest of Berserk.
Although, with your explanation, I'll gladly revoke my implication that it was pointless. There is some emotions to be had, and some sympathy to be given to poor ol egg man. I'd probably tell my life story to some stranger too if I were in his situation. #ProofOfExistance