Good point, typically it is not the bacteria/fungus that we digest when say
eating food gone bad that makes us sick. It is the toxins they produce and
release into the food. This is an adaptive response to avoid competition.
That is why it is not a good idea to just cut away the green bit of cheese and
eat the rest of it, the toxins often spread beyond the green area. Hence, the
"bugs" just make the food toxic for other critters so that no one else will
eat it, but of course it is not toxic to them. It's kinda like spitting on
your food to prevent other people from stealing it (as long as they don't spit
on it either!).
Tootles
Peter