I myself have not left when I  have seen girls party mainly because it was not obvious when entering their place and they brought out their party favors later in the session.

There is no need to name providers but for those who have seen many, from top notch/traveling expensive girls to local girls advertising on the BP, CL, etc. and even the local paper, how many times have you seen them bust out the favors or pipe to smoke substances that clearly are not an herb?  

Analyzing my experiences, I would have to report that I have seen about 10 girls bust out the party.  Out of the 10, I'd comfortably say that 2 are vintage ts porn stars and the rest were local girls on CL or the BP.  

One time visiting San Fran, I met a girl on the street walking her dog.  I followed her hot body back to her apartment.  She took my money, some dude peeked inside her apt.  She then exchanged things with him and started smoking.  I sat there while she did that for about two minutes very uncomfortable.  She then opened an old pizza box, took a bite of a slice and fell backwards passing out.  I quickly left

The above was many years ago.....I am so lucky that I never had any problems and am no way going down these streets again.  While I enjoy TS fun, I am not interested in any type or risk

I personally am not so I do not see the girls that are obvious about it.  

I too have been in a house when the girl starts to pull out the party. It's a major turn off.

And please dude,  try not to be naive. These girls are not your exactly ' girlfriend' and only see you.
There are many type of guys they actually meet. For them, It's a business transaction.
The more they can  provide, the more they can get.
Just because they don't put party on their ads, it doesn't mean they don't party, vice versa.
Some guys love to party and some guys don't.  
It's actually a smart way of them to market themselves.

I asked the 'party' questions to some girls and they actually gave me real good explanation about it.
"If some clients love to party and these girls have the party flavors ready, they actually make more money and steady clients".
And for some clients who don't party, they don't have problem either."
And to remind you, dude. You're just a guy who loves to fuck and nothing more just a client, among other other clients that they have.  So, chill...