MATL chunk bloats size on each .vox file?

[aardappel]

Seems the MATL chunk adds a fixed 40k overhead to each .vox file now, even on small 8^3 models that would have otherwise been just 2k or so. This is on models where I've never done anything with materials, its all just default diffuse, default palette. Is there any way to turn saving of this chunk off? Or, err, optimize it?