I have been in the hobby for 7 years. Before that, I occasionally visited AMP's like the Captain. In all the time I have been visiting K-girls, I have never seen any indication that they were coerced. In fact, I have had close relationships with a few where I would ask if they wanted to go somewhere for the weekend and they said they would just tell their booker that they were taking off. So they are truly independent and are not being muscled around by anyone. The booker is merely the middle man that does the screening to make sure the girls and the customers are safe. Some of the top agencies may seem like they are strict with the girls, but the girls follow the agency "rules" voluntarily because they tour and want to be able to come back, and if they flake out on the agency, they won't be able to return. Many of these girls tour independently all over the country. I have seen the same girls in various cities, from the Seattle to SD to DC. I just happened to be there when they are as well.
With that said, there is obviously some exploitation in the business, but this most often is associated with Chinese, Mexican or Russian/Eastern European shops, and coincidentally, these are the ones targeted by LE, so if you visit these places, you have a more likely chance of being there during a bust. LE is most interested in organized crime types. If you stick to independent K-girls, in my experience, there is no exploitation and they work in this business because they want to. Some have told me that they start doing it because they have to help out family members back in Korea. There are various scenarios, such as the father died and the family has no income, aging grandparents need medical care, etc., so they come here because the money is good. Once they are here, it becomes a preferred lifestyle because the money is good and they live pretty well. There is a K-girl community and many of them text each other and share info about customers, so you would do well not to trash any of the girls to other girls, or they may find out.
If you do some research, you will find estimates that as many as 25% of all Korean women work in the sex industry at some time in their lives (includes massage parlors, night clubs, strip clubs, etc.), so it does not carry the same social stigma that it does here. They even have a "university" where many of our K-girls learn the finer points of their craft that make all of us such happy campers. I have even had a few girls tell me they did not learn everything yet because they did not have a chance to go to "the school" in Seoul before coming here.
So the bottom line is, if you stick with the K-girls that advertise on the various websites, it is nearly 100% certainty that you are not seeing someone who is being exploited or forced to be in the business. Its their free choice. Some may be "forcing" themselves because of their circumstances (hence the occasional girl with a bad attitude), but no one else is forcing them.