Lol, the "pull factor" is just money. It's the same reason a lot of Japanese people would want to get regular jobs in America, 150k is like baseline in major US cities now.
I don't do escorting stuff in America because I like to go raw and I believe it's safer in Japan, but I have some finance friends who are seriously deep in the US scene. My friend even "dated" one of the popular girls and found out she made between 270-300k a year, CASH. If you don't understand taxes, that's like making $550,000 USD from a salaried job. Another girl, who was actually a bit older, maybe 32-33, was booked by an older guy for THREE MONTHS at a rate of $3000/day. Yes, she made fucking $270,000 in three months just living with this guy. She got to live in this luxurious 20 million dollar house, eat the best food, do whatever she wanted, and all she had to do was fuck this guy whenever he wanted.
That's fucking ridiculous. I seriously cannot believe this shit, it's so funny.
But anyways, if those girls report the mamasans they'll also get banned from the US themselves. Immigration knows this kind of stuff happens and they do try to stop it