would honestly expect most other men to genuinely refuse this offer if actually presented with it.
That's more of an issue with making sure that the logistics work right - the prior for someone going around with a million dollars to spend to get straight men to sleep with them is so low that "this is obviously a scam or a ruse of some sort" eats up the remaining probability mass.
Imagine instead of some guy coming up to you with the offer, you get a phone call from your attorney. He says he is in the room with some %celebrity's attorney with a million dollar check on the table, and lays out the offer for you.
A long blog post explains why the author, a feminist, is not comfortable with the rationalist community despite thinking it is "super cool and interesting". It's directed specifically at Yvain, but it's probably general enough to be of some interest here.
http://apophemi.wordpress.com/2014/01/04/why-im-not-on-the-rationalist-masterlist/
I'm not sure if I can summarize this fairly but the main thrust seems to be that we are overly willing to entertain offensive/taboo/hurtful ideas and this drives off many types of people. Here's a quote:
The author perceives a link between LW type open discourse and danger to minority groups. I'm not sure whether that's true or not. Take race. Many LWers are willing to entertain ideas about the existence and possible importance of average group differences in psychological traits. So, maybe LWers are racists. But they're racists who continually obsess over optimizing their philanthropic contributions to African charities. So, maybe not racists in a dangerous way?
An overly rosy view, perhaps, and I don't want to deny the reality of the blogger's experience. Clearly, the person is intelligent and attracted to some aspects of LW discourse while turned off by other aspects.