That could be a pretty decent hobby for the wealthy who runs out of things to stimulate.

Part of the problem is that older guys might sometimes get tired of their wives, and surely wives might even retain a lot of those similar kinds of resentments.. at first she does not really say anything in public, later she denigrates and later she figures out that it might be better to just allow for each to have their own space... and for sure, if you want to retain a wifey relationship, but you do not want her to be the "s" out of the "s&m" interactions, then she might be so kind as to look the other way, and to allow you to maintain your own space for such... including since many of us are likely to evolve into more and more bitcoin richie (so long as we do not die to early to be able to enjoy), then spending some of ones excess wealth on such extravagances might not be a bad plan or practice.  just saying.

I am not going to try to judge you too much based on: 1) how you choose to spend your wealth (especially once you have likely reached multitudes (if not magnitudes) above entry level fuck you status, 2) if you happen to enjoy some of that infliction of pain upon yourself and/or 3) your potentially leading some untraditional ways of interacting (surely that is if you can get away with it - because sometimes it can be quite difficult to actually find a way to allow our most extreme fantasies to play out).....

By the way, on that last point, there might be some willingness to assert that "I don't mind paying for the services that we agree to", but then even if we might be at magnitudes above entry-level fuck you status, we might not be very accustomed to "transactional relations," so in that regard, even if there might be a "transactional relationship" going on, we still want to attempt to maintain a kind of appearance that the relationship is not transactional, and creating those kinds of relationships might not be very easy to accomplish...   Am I talking from experience?  not going to get into those kinds of details, at this time.

By the way, one of the difficulties of having that long-term spouse relationship may be some of the possible "being discrete" issues because the wife might not completely mind if some of the side play starts to happen, but she may well not want to know details or to have anyone who she knows to know such details either.. in order that she can maintain face.