Yeah, exactly - or there's a version of this fantasy where the staff ARE paid but they're all one big happy family, which you see in things like Hallmark Christmas movies and the Lindsay Lohan version of The Parent Trap and I think Downton to an extent, too.

IDK, I think it's not a bad idea to point out that historically any sort of residence and property like this was only possible through gross exploitation, whether it's slavery or some other form of serfdom or indenture. Regardless of how aware they already were, it should be possible to turn the conversation to that. But pointing it out in passing or casually should be okay, because once they think about it most people would realize that it's true.

Also there are modern experiences in the hospitality industry and in stately homes preserved as museums and for historical value that don't always show, or even hint at, the labor involved.