Anaphylactic shock is extremely rare. And even in cases of anaphylactic shock, it's only fatal in an even rarer number of cases (which makes sense, anaphylactic shocks is a biological reaction of your body to save itself, not kill itself).
We really don't know how many lives emergency epinephrine has saved, but it may have only been necessary in less than 1 out of 50 cases. However, it benefitted the manufacturer to overemphasize the prevalence of dangerous food allergies and the risks of shock and encourage doctors to prescribe them in increasingly more "just in case" cases".
It's in this world that parents and doctors alike became insanely cautious and paranoid about introducing allergens. Conveniently, we saw the rise of simpler, more highly processed baby and childrens' foods at the same time.