Because clay is so hard to find on the beach, this reduces the potential of bricks as building blocks. To make clay more common, there should be underground clay deposits similar to the patches of dirt and gravel.
Yes. I have on,y found one deposit of clay in all of minecraft. (since beta 1.3...). I only got enough clay to make 4 brick blocks, when, in building terms, that is not very much. for this great idea.
Underground Clay Deposits