Heh ... not much advice to be given I guess. If it is something people need to be cool with, there isn't much to be done other than asking if they are or not and going from there.
The very fact that some people are scared away by this is what makes it a kind/fetish. I suppose the best I would offer is that, given that meeting people is kinda difficult for most folks regardless, we should make the most of social spaces like these where people get to make it clear what they like and want. If I can talk to someone about things in a safe way and describe who I am before getting into things, it makes it easier IMO. Definitely not fun to get into things with someone only to discover after the fact that there are issues with accepting each other.