Is ‘as’ unavoidable?

The following passage is from the website as follows:

http://www.epubbud.com/read.php?g=H8AVF5J5&p=8

But in practice, people usually offer close to half the money. Generosity seems to come naturally, or rather, ungenerous behaviour is irrationally foolish, because the second player will – and does – consider a derisory offer worth rejecting, if only to punish the selfishness of the first player.

The lesson of the ultimatum game and hundreds like it is that again and again people emerge from such experiments as nicer than you think. But the even more surprising lesson is that the more people are immersed in (the collective brain of) the modern commercial world, the more generous they are.

This text is talking about so called ‘the Ultimatum Game.’

What I want to ask is ‘as’ in the underlined sentence.
I don’t see the inevitable reason of the presence of the word.
It seems to be used to coordinate with ‘such’ but I am not sure why ‘as’ must be used.
Let me tell you why I thought so.
The sentence in question can be paraphrased as follows:

The lesson of the ultimatum game and hundreds like it is that again and again people emerge nicer than you think from such experiments.

First question:
Am I right with this paraphrising?

If this is right, I don't see any unavoidable reason that we must use ‘as’ in that place.

Second question:
Is it all right that I take out ‘as’ in the sentence?

And last question:
Even though the sentence is OK without ‘as,’ the author used ‘as’ in that sentence to coordinate with ‘such’ in that sentence.

Thanks a lot in advance for reading this long post.