Something tells me that something has changed in Corona and not in the 3ds Max. I have character that i've been rendering since Corona alpha 5 and if i open this character in V8, the trick with making base mesh non renderable via object properties is working, i.e. the mesh itself is not rendering, but the hair that grows on it, is rendering. I can't make it work like this on freshly created mesh though.
I checked this back to Corona v5 and it has behaved the same all along.
I think you need to roll back even more, possibly to V1.6 when there were no hair material.
I can log this as a bug, but the behaviour seems logical to me. If the base object is set to non renderable then the modifier shouldn't be rendered.
Using low-poly non-renderable mesh for growing hair is pretty common with CG characters. I think all the renders that i've tried, supports rendering hair from non-renderable mesh.