How can you be 100% sure that those are false percs and not true ones?... Not all true percs have a black mark in the middle.... What's a sure fire way of knowing?
And yes it is perfectly normal for clowns to host other corals instead of an anemone. Other good hosting corals include, various leathers, bubble coral, elegance coral, or mushrooms...etc. I've heard of some hosting a protein skimmer intake!