I agree, no gasket. Mechanically, I'd want a solid metal to metal contact. I did put a trace of RTV there though, for sealing.
There IS supposedly (I think) a gasket between the brake backing plate and spindle, but I also did not like the fact that there would be a paper gasket somewhere between the bolts holding the spindle on, so I just skimmed some RTV on the backing plate and eliminated the gasket.