OP, I can totally relate to your post.
The unexpected car repair, vet bill, dental repair, etc. never bothers me. In fact, I kind of feel empowered that I can just handle it without a second thought. It's like life is throwing me curve balls but I can handle it.
Honestly, I tend to stress more over the irregular, flexible budget items. My furniture and wardrobe desperately need updated, but I'm too cheap to spend the money. What if I need it for one of those emergencies?