To prevent it from breaking down when dipped into the soup. Try it for yourself.

When you squeeze, it makes it compact and remain solid after wetting it in soup.

Otherwise, as you lift it into your mouth, it will break half-way, dropping back into the plate, splashing the soup onto you!!

To remove the air inside.

its part of the process...to whet the apetite and act as speed govenor esp for shared meals

I concur.

foreplay