The Ecology of the Goa’uld

(Non-sci-fi-nerds.. just turn away, this is the sort of thing you probably beat up kids in high school for talking about).

So I’ve been re-watching Stargate SG-1 (Wikipedia) (IMDb) on my morning and afternoon commute, and something has been bugging me.  I dug around on SG-1 fan sites and couldn’t find a satisfactory answer, hell even a discussion, of the topic.

Throughout the course of the series we encounter maybe a dozen Goa’uld – the System Lords. Which gives us the impression that Goa’ulds, in hosts, are uncommon. This would make sense as well, since the Goa’uld fool everyone into thinking they are gods, and there can’t be a lot of gods.

But we see literally hundreds of thousands of Jaffa throughout the show. The Jaffa carry, in their bellies, Goa’uld symbiotes that are maturing.

And so my question is:  Where the fuck are those symbiotes going when they mature?

Sure, some of them are dying – en masse – in various conflicts. But surely some of them are surviving, reaching maturity, and … then what?

At the rate symbiotes are growing inside Jaffa there should be planets full of matured, fully hosted, Goa’uld (just, presumably, ones who aren’t System Lords, and aren’t going around pretending to be gods, unless the faithful are supposed to believe in a pantheon of a billion all-powerful deities, which would strain credibility.

Why have we never even heard of this society in the course of the show? It seems to be a glaring plot-hole that I’m just surprised nobody has mentioned before. I feel like I must be missing something.