We eliminate those parts by using only the stem-end flesh, and discarding the half containing the seed cavity. We can be wasteful because the butternuts are such heavy producers. The half of each butternut that we discard, feeds our cardinals over the winter. They love the cooked flesh and the seeds. All of our neighbors' cardinals belong to us now.
Butternut squash has more beta carotene per ounce than pumpkin.
A pumpkin grows by expanding its outer shell like a stuffed politician, while the butternut delivers solid flesh and flavor. A hail or wind storm can flatten a pumpkin patch, while the butternuts hardly notice. I have been growing the Zenith Hybrid from Stokes seeds for many years. They average 4 lbs. and while slightly smaller than the popular Waltham variety, are much heavier. Another one to try is the Ultra Butternut Hybrid which is twice the size and three times the weight of Waltham.