Why destroy Laketown's bridge?

[Sauron the White]

from davem

Smaug's intent was to enter Lake Town on foot but he couldn't do that & had to resort to an aerial attack, making him vulnerable (Tolkien is clear that his only point of vulnerability is the unprotected spot on his left breast - not his eyes).

please.... Please.... PLEASE ...... somebody just quote directly from Tolkien in the text where it clearly says that
SMAUGS INTENT WAS TO ENTER LAKETOWN ON FOOT.
I beg you. I implore you. I humbly ask of you. Show me that in black and white.

Not your suppositions.
Not your conjecturing.
Not your musings.
Not your assumptions.

If you state something so emphatically that it is presented as fact, please present the support in the text for that as a fact.

Otherwise, it is merely your assumption, your belief which you certainly have a right to. You decide to make a deliberate choice to see it that way despite the absence of any clear presentation of that conclusion as a undebateble fact.