Rediscovering Genesis

I have only read Genesis once in my life and even then, I probably did it quickly. I don't think many Christians read Genesis because they are ashamed of it. People have looked at me like I am crazy when I say I believe Genesis is real. The book is made out to be a fairy tale and ridiculed by scientists the world over. Anyway, I still believe it. Besides, the Psalmist in Chapter 14 says 'the fool says in his heart, "There is no God". I believe that too.

Anyway, within half an hour into Genesis, I came across two possibilities that I never considered before. These possibilities (in the whole scheme of sin, repentance, salvation and judgement) aren't important. But it's good to think about unimportant things from time to time:

Did God create more than Adam and Eve?
When Abel got himself perished at the hands of Cain, God drove Cain from the land. Cain was to wander the wilderness, separated from his family line. Cain protested by saying in chapter 4:14 '...I will be a restless wanderer on the earth, and whoever finds me will kill me'. God responded by saying 'not so' and put a 'mark on Cain so that no one who found him would kill him.'

That reads like that there are more family lines out there that don't belong of Adam and Eve. Some commentators say that Cain was thinking about the exponential growth of Adam's line and he was worried about running into these future people. But Cain's worry sounds like it was of an immediate nature. Cain went East. Could it be possible that God created people in the region of Asia after he created Adam and Eve? Adam and his descendents would have had to breed like rabbits to fill the world as quick as they did. Granted, Adam was still having kids at 130 and lived to 930, but surely he was running out of lead in his pencil by then!

Further, who would interpret the 'mark'. Already existing intelligent beings would be the obvious answer to me.

Was everyone before Noah a vegetarian?
I hope not. If Adam was still dishing out his seed well into his hundreds, surely he needed to do so with the power of meat. But after the flood, God made a covenant with Noah and said in Genesis 9:2:

'The fear and dread of you will fall upon all the beasts of the earth and all the birds of the air, upon every creature that moves along the grounds'...you get the point.'
'Everything that lives and moves will be food for you. Just as I gave you the green plants, I now give you everything'.
Was everyone prior to Noah a vegetarian? Abel had flocks and gave the first born to God as an offering. Please, please tell me Adam, Abel and his family were chewing the fat? It would be tough to acknowledge the existence of vegetarians in the Bible.