In fact, I think SPs are the ones that tend to be more understanding of my going "There was a snake! It was there! I got scared and reacted," while some of the ESJs (usually the very calm, cool ones) shake their heads and claim I should trust the school enough to assume they wouldn't let a dangerous creature into the building, and are disgusted that I "allowed myself to be controlled by the situation."
Perhaps there's more than one kind of SP... the one that enjoys the thrill of danger, and the kind that fears/avoids danger and wants to remain in relative comfort like I do (but is happy to indulge in stimulating experiences that don't involve danger, pain, or risk). I have a feeling I'd get along better with the second type of SP.
After reflecting further, I think it might have more to do with enneagram instinctual stacking than type. For instance, an SP with a stronger self-preservation than social or sexual instinct might very well be less bold than other SPs.
I suppose the main thing that's consistent about SPs, is that they have a strong reaction to their physical situation. They either seek out danger, or they're absolutely disgusted by it. Not as much in-between.