A couple of times, yes. When I was about 20 (and VERY broke) I was offered $20k by some guy to impregnate his daughter. I said "hell no" and that was that. I learned later that he was from some colony (similar to Amish, but allowed to use technology) and they frequently do this to try and expand their gene pool to avoid inbreeding. A few years after that, I was offered $100k to marry some woman so she could stay in the country. That was also a hell no.