I think we all do it because it is practical, functional, no strings attached, usually minus the mind gamesand when it's all done, you just walk away, no fuirther costs, no fuirther commitment, no further hassle. Well, normally - yes there are stories of those mind games being used to defund the punter, and I am sure there have been cases of extortion.. but they are in the minority...
The question is what drives us to punting.. from what I read, it is because of the deadbedroom (or lukewarm or just can't get enough in the bedroom) syndrome, the fulfilment of fantasies that can't be got with most civvies/existing partners, being single/without a partner, being able to do better than one perceives they can (younger, fitter, etc)..
Mine sort of spans all of them... well sort of.. Siberia is warmer than our bedroom, the partner is very vanilla and average at that (as I recall.. has been a while), I engaged the services of one SP for one fantasy (which I didn't fully carry out, but when lockdown is over, I have found what looks like the perfect SP to finish the job), and I seriously doubt I would score on civvy street with many in the worst wogking girl photo thread, so it means I can, with a text and cash, at least sample what I am missing out on.
I have had the chance for a couple of affairs - but they are too much hassle. One was divorcing, and the other was in a relationship where he didn't want to settle down.. So, both were a hiding to further misery and dependency - on me.. Although my punting has been thin, once the jab is done and we are most way to normal, the bank account will be hammered (for a while) and my review count should go up!