I think you absolutely do need someone/some team/some organisation playing the role of architect on a system. I've blogged my thoughts on this here:

As to why do people become architects - I'm guessing there are a number of less cynical reasons - perhaps for the challenge, perhaps simply because a position becomes available. For me it was the frustration of working on systems which had a feeling of being a mixed bag of different ideas and techniques to solve the same problem.

I haven't come across any architects that don't code - I certainly would expect architects to still be involved to some degree in coding whether it's simply prototyping or working on core parts of the system which utilise new technologies/apis and need to be integrated/tested to mitigate any risks.