Where did you get the seeds/starts? If they were from a seed saver instead of a commercial seed grower, he or she may have been growing different varieties and didn't have them sufficiently isolated which would result in cross-pollination. The fruit of plants grown from such cross-pollinated seed would exhibit a lot of recessive and unusual characteristics.

We usually grow four or five varieties of summer squash that bloom at the same time and cross-pollinate like crazy. We don't save or intentionally plant the seeds, but a few volunteers will pop up in the compost pile every year. They are some weird-lookin' squashes.