If white doesn't have an extension somewhere around a, I don't think he will normally extend at b. However there are some cases where it is not a bad idea.

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In the case that white already has the extension, white can play at a, if Bb Wc etc. white is very happy with these exchanges, since black has no good follow up on the bottom.

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If white doesn't have some backup around a, then I think it is normally considered a mistake for white to play at e. White can either play some extension around a, or play Wb Bc Wd Be if he has some potential for a moyo on the bottom.

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With this being said there are some board positions where it is not a bad idea to play the "inferior" way. Part of being good at joseki is being able to imagine them in relation to the whole board. I have seen some professional games with this shape, but it's probably not very common because it's normally a mistake.