If they were surrounded by these things every day of their lives, I think extreme caution (always being aware of where the one closest to you is at the moment) would become second nature very early in life. At the same time, I suppose they might have taken the pain(s) as a fact of life; An accidental multijabbing that would reduce me to a blubbering infant might have been a minor annoyance to a native.
I never traverse desert wilderness without tweezers & backup tweezers. I wonder if early desert dwellers had their own techniques to remove cactus spines, glochids etc.?
