[Crash Ichimonji]

If by 'open-minded' you're meaning 'bored and need something new all together', then I'd see that being a plausible reason.

Example:

TG and simple DTG used to be really kinky for my co-author's and my RP's but then we needed to try different variations on the fetishes. Guy-turns-to-girl may be a staple for many, but for us we gradually needed to find less common (or just new all together) forms of gender-bending. So again, it's kind of a jaded and bored thing with us. On a funny note, last year my co-author realized she might be a closet-fujioshi.

I've gotten more into S&M thanks to reading a little of 'Nana to Kaoru' and 'Demon Candy Parallel', so the increased-exposure thing works as a plausible explanation if that got you into something new. Even outside of fetishes that's true in lots of things people take interests in. Radio disc-jockeys are bored out of their minds playing a recent hit song by the time it REALLY resonates with the public and sometimes it takes more than mere pilot episode to get people finally interested in a series on TV.