It used to bother me about the waste of fabric when PP as well, especially when something like this which will use so much fabric. But the perfect points and crisp lines are so hard to resist.
If I'm paper piecing with odd shapes, like those triangles, I print the templates and cut each piece out with an extra 1/8th all around. That gives me a little extra for misalignment issues (check it out, my issues have names! ;-) ) with minimum wastage.