Well...

..... for someone like me (I have a rather open and extensive menu also) ...and fingering doesn't feel that pleasurable it's really that simple. And too many that want to do it  don't wash their hands first and their nails are too fricking long.   I sort of think you arleady knew the answer that it's personal preference for whatever reason.

Funny that you bring that up and I think it all about provider preference and you also have to consider the volume they may handle and all the lil variables involved that may be health/ lifestyle risks. A lot of things I am personally comfortable with and some I def am NOT even with the enticement of cash involved. I consider myself pretty open sexually prior to this career decision and if the random guys I've done things with didn't get it, well, you, the client ain't getting that either! But, if you have a reg who is pretty open and accommodating, I think like in any relationship, boundaries may be explored a true YMMV approach to what is acceptable and what is not may happen over time.
I actually encountered a guy that wanted to debate why I may allow a CIM but won't swallow. Really though? I told him if he showed me how to do it first I would def follow suit! Very happy that he did not call back or try to persuade me, there are plenty of ladies that allow for a lot, even BBFS, and man, they can have that money, I'm cool!

I have had providers who would on some occasions but not on others depending on their mood.  I make a point to have nails trimmed short a day or 2 ahead & have been known to bring soft soap & hand towels to a appointment.  "You want to put your fingers where?"  "They d*mn well better be clean."  Even so, if she allows DATY, I will see if she will accept a finger.  But I look on this as I am the motor but she is the driver & I go where she steers me.  I enjoy pleasing my partner, and sometimes I've gotten lost I'm my enjoyment of her responses & taken her through a whole series of Os...  after, she is so relaxed that she can't effectively squeeze me & has trouble getting me to Cum.  
Providers who don't like cum on them anywhere should find another line of work.  
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