Tomatoes with the designation "San Marzano" do not have to cost a ton. "San Marzano, D.O.P" can cost more, but there are bargains to be found. And there are plenty of terrible tomatoes from San Marzano and great ones from other sources.
Never heard of dough with only oil and no water. Anything is possible, but either the server was pulling your leg or her boss is having fun at her expense.