Markets used to (still do on a much, much smaller scale) where you could get these people from across the ocean and BUY them. Yeah, and then they became your property and you could make the work in the fields for you, or clean your house. And you just had to house them, maybe a few rags for clothing and if you were really generous, you could feed them. What a great market that was!! A market exists, it should most certainly be legal.
However, watch the show cathouse on HBO, and let me know how many of these girls with their own homes, cars, health insurance and 401k plans are being treated similar to slaves?