A late-20's provider who I saw today (my first time with her) asked me an interesting question - "I don't understand why I only get married guys, hardly any single guys"  
 
I don't think she was looking for a single guy to hook up with. I think her question was sincere - she was genuinely puzzled why married guys who have a sex partner outnumber single guys who don't.
 
I told her that I will ask the community. I assume she will be interested in your answers.  

For whatever reason the wife has closed the store...illness, not attracted to the husband anymore, was never really that into sex and dropped it as soon as she could, menopause, husband wants shit she won't do, she stopped doing shit he liked (BJ comes to mind)

married guys pay women to go away and be quiet.

A good wife is a life partner.  She shares responsibilities raising the kids, paying the bills, saving for retirement; she even does a great job taking care of hubby when he is sick or needs a hand.  On occasion, the husband may be looking for another woman to fulfill a fantasy. A single man can cheat and only risks a break-up with his current girlfriend.  A married man that cheats risks a messy divorce that will change everything in his life.

This is the perfect answer to the OP question.  

I'm a 28 year old single guy so I know I don't fit the profile of the typical client.  I'm an IT Engineer and make a decent salary, and I think I'm a decent looking guy.  Think big bang theory type, if you've seen that show.  However I have never been able to get women on my own because I don't have much social skills.  I hate bars/clubs and being around a bunch of people I don't know.  I'd much prefer to be home and mess around with my computers in my free time.

Many women lose their sex drive with age- if they ever had any.  

they can afford to.

Younger guys find it easier to go out and play the field to get the pleasures they want. Older single men would rather pass on the games. Discretionary money is another issue for younger men who may not be able to budget and afford to hobby.

It's really simple, A NSA with a provider, an affair which includes emotional element, or celebacy.  I made my choice.  
SO had no sex during a long interval when she was widowed...  said she could "take it or leave it".  I mistakenly thought she was willing (and genuinely enjoyed it) when in fact she prefered not to.

Why limit yourself to one woman in life?
Just enjoy yourself and most providers don't care either.
They are probably in the same position whether dating or married themselves.
I don't care if it's inside or outside this hobby.
It's not that hard to be upfront and say this is what I want in my life.

1) There are roughly 8 or 9 married men looking to cheat for every 1 married or single woman looking for the same.

It sounds like your relationship with your wife has evolved into the type of relationship you would have with a live in sister or close aunt. It happened to me, I recognized that I was no longer sexually attracted to my ex and she said she could tell a year or two before I brought it to her attention. Instead of both of us staying in a dead sexual marriage we decided to part on friendly terms. It was the best thing we could do as we are much better friends than we were lovers.
I'm fortunate that I'm in a recent relationship with someone who is the best lover and friend a guy could want. She's ruined me in a way that I stopped seeing other women and I only want her...
Best of luc

As Big Al would have said.

I understand all the pragmatic arguments such as: "I don't want to jeopardize my marriage and family, and providers give me what I need." "older guys have money and they can afford it", hobbying actually may even save marriages", "single guys can pick up (really? ask a single guy and you'll be surprised how little he gets)" blah blah blah.  
 
I think there is another important factor: the thrill - thrill of cheating, thrill of living on the edge, thrill of doing something that, if exposed, can potentially ruin your life, and maybe even punishing your SO for "headache" the night before.  
 
Yes, there are the pragmatic arguments, but I think there are also a lot psychological reasons - for  
single guys, the social cost of being caught is a lot less, so there is less of a thrill. For married guys, hobbying serves lot more than the physical need.  
 
Well?  

And possibly subliminally true for many guys...the "stick it (not literally) to the SO" for neglecting them.