You don't need to be so literal. When you look at honeycomb, for example, the manufacturers provide strength data in much the same way you'd see it for a solid metal. When you model it with finite element software, you treat it as an monolithic material - you don't model every fold of metal. In that sense, honeycomb (and this stuff) is a material in that it's used the same way. The properties of the "material" already account for its micro-structure.
