So let me clarify.  Briefly:
1) I think that most guys would be intrigued if they received a simple PM from a lady that merely indicated that she thought that we might connect or that you might be a good fit [for her].  Nothing too extreme or weird.
2) If I were a provider, at times I might want to read reviews or basically have more of an influence on who I see.
3) I would think that direct, tailored marketing such as this would be an effective and efficient way to build a solid client base.  After all, targeted marketing is a best practice.  
4) I am sure that providers communicate with each other.  I am sure that some ladies (while respecting privacy)  talk about guys.  They can't rate guys, but they can white list a guy (whatever that means).

I don't pay for VIP, the only time I have it is when I win the sports contest and get free days. If a lady were to PM me, there's a good chance that I won't see it.  

Off the top of my head, I've had 3 ladies PM me.
1, I'd probably see
the other, I'd probably see but I'm not in her age range and she isn't in my general range
the last, I probably wouldn't see, she's just not my type.  

For me, a lady is better off posting an ad/pics than PMing me

I think most of the women on this site who reach out through PM'ing do so at their own discretion, thus "private message".  I cannot speak to why they choose to PM someone.

If there is someone you're looking to spend time with, simply contact them.  Just my .02

Because we already have websites and interact with potential clients via twitter and the boards. PMing random men is like door-to-door sales. You don't know if you're someone's type/ you fit their budget/ most probably won't respond because they aren't VIP, etc. If you're interested in booking a lady simply contact her, it's ridiculous to think that she goes around contacting every man in her city to drum up business.

I think the ladies are a bit afraid that it would seem desperate so rather than reach out to guys almost at random they wait for a gentleman to indicate interest first.

Having said that I have had old friends reach out to me. I have also had so.me inquiries about jazz and one or two situations where a lady felt I needed to know something about another member of the community or some story circulating I needed to be aware of.

But out of the blue marketing messages ----no that has never happened.
.

That shit sounds annoying.  

questions like this post.
I have received PM's from ladies from California to Europe as well as some of the beautiful local ladies. And I might add I have seen none of them, although were I still in the hobby I surely would. But alas I'm no longer in the hobby because of an incident last January. I just stop by occasionally. The ladies here don't need to troll. They all are beautiful and unique.