Why destroy Laketown's bridge?

[Macalaure]

Originally Posted by Sauron

given the very flat and wide nature of the docks

We seem to have a different kind of perception. If I look at the illustrations, I do not see docks that are very wide. I see docks that, without the houses and the close vicinity to water, would be just wide enough for him to land.

About the picture: If it wouldn't show something which is contradicting to the book, nobody would be willing to discard it. You seem to try to use the picture in order to disprove the book, which is - I'm sorry - ridiculous.