The litters thing is new... it used to just be that Orks had a short gestation period (6 months, IIRC), and were generally poor, so their only entertainment was, erm. Baby-makin'. So, they usually had a half dozen kids, which lead to racist talk about "litters" and the like.
It's only recently turned from "Racist chatter" to canon. Which still weirds me out.
As for wealth, there's also the odd notation from Socio Pat a decade and a half ago (so ... old ...) where he noted that wealthier families were hit with UGE for Dwarf and Elf kids, while the poor were largely hit with Goblinization. In Shadowrun, the poor are simply more likely to be tusked while the wealthy are more likely to be pretty.
Which is an ... interesting ... lesson.
(You'll find that the south, for instance, had a larger-than-usual Ork and Troll population, with Appalachia having almost 10% Troll, the highest in the former US. The northwest had a larger Elf population. Dwarves don't seem common anywhere. Oh Dwarves, so easily overlooked.)