TL;DR: disgust is learned.

• How Do Toddlers Learn About Disgust
• Is moral disgust socially learned?
• Disgust as an adaptive system for disease avoidance behavior

Bottom line is that while there are things that we're hard-wired to reject, the rest is more about what social groups teach us at a young age. Also, we can overcome the hard-wired aspects to an extent, again through social reinforcement.