If a Bedouin lifestyle could feed the kind of population density we see in modern oil-fed countries, then there would be that many Bedouins. But it can't, and there aren't.
The bottom line is you just can't produce more meat and milk than the region's plant biomass will support. This is true everywhere, unless you artificially increase plant yield by irrigation and fertilization--which brings you right back to the original problem of reliance on fossil fuels for growing food. I'm also not willing to say that we have the right to displace or hunt to extinction the huge herds of wild grazers that already occupy those grasslands not being actively managed by humans, just to feed more of us.