Block textures often don't need to be set so perfectly. I mean.. who cares if it does not fit perfect around a 9 degree edge? It could be just build like this around the edge. And finally when it comes to a top-plane, too, you'd have to use a "wall" and "top" texture to fit both. If you have it, it is easy to texture with blocks, if not, nobody cares, too.
If you stick to a few rules with blocks you can get nice texturing in no time, and for the more complicated parts you can still use models.

Take a look at this example of a combination of blocks and models, the block texture fits without the need to change the settings of the faces (for none-90-degree-blocks, too).