Being Latvian i'm making the connection with Kaite_43 who was in the area for well over a year. I have seen her twice and she didn't seam trafficked.
I'd say all of the ee's I have seen are here to make money. They may well be part of an agency etc but they are here as it is the best £ per hour / work that they command.
I always remember the example of Lovely Katty. She started off in Lower Ford Street but felt that they didn't do enough to find her work and it was a rip off, so on her 3rd or 4th visit, she left them and set up in the Britannia in Fairfax Street, just 2 minute walk over the car park. When you Tinyeyed some of her pics it took you to a blog where she was showing off a load of clothes and girly tat she was into, which is probably why she needed this line of work.
I also remember Cindy, who didn't last long in that group, they told her to put her rates down to £50 and £70 from £70 and £120, but she wouldn't as she thought she was worth more (she was to be fair
)
I also noticed this year that a lot of EE's were away for the whole summer and have suddenly come back again Is this because they have kids on summer holidays from school?
As mentioned previously, keep an eye and ear out and report where you feel necessary, but don't be a total Nigel and paint them all with the same Sergei brush.