While I'm sure that there are a few people who are in a position to be able to take their fantasies to the extreme and may do so, for the majority, these sort of fantasies are just that- fantasy.
Even the studs have the same real life considerations to deal with that the women and couples do. Jobs, ******* etc. prevent them living life as full time "masters" just as they do the "slaves". The majority of owners "own" their slaves under defined, negotiated terms, maybe they get together every other weekend or whatever to do X,Y and/or Z.
More importantly, all this master/slave stuff is fantasy nonsense except for the few of us that actually do live in full time D/s relationships, but even then real life D/s looks little like the flights of fancy that most of the dreamers post about on these websites. Believe me, average full time D/s is not much different than a traditional "vanilla" marriage with the exception that both partners have chosen that one of them is the leader and primary decision maker.
Sure, we have protocols that are established to govern basic conduct and rituals which may set us slightly apart in public as well as private and we might play kinkier games than many others, but that's what it ultimately is- playing games. My Wife might call me at work to tell me what she wants me to do when I get home, but she would never command me to take a day off from work just to "play". Our fantasy life exists within and as a part of "real" life, NOT in place of it.
Being Mistress and slave does not suddenly make the need to earn a living, pay taxes, do housekeeping, auto repairs, etc., disappear.
At the end of the day, my Wife is fully aware that, while she "owns" my love, adoration and devotion as well as my obedience within our negotiated limits, she doesn't really "own" me.