I appreciate what you're trying to say, yet - pic related. You don't hear about the ass fetish predator or the boob fetish rapist, as those are considered to be naturally attractive parts of the female body. But go search for 'foot fetish predator' and you get a tidal wave of news articles and blog entries.
That's not what I'm trying to get at, though. I don't think foot fetishists are oppressed, but we do get bad rep from degenerates and if you tell someone straight forward that you like feet, there's a fair chance they will look at you funny. Imagine going up to a female friend and telling them you're into bondage. Same thing, there's no telling how they might react.
Sure, if you're attractive, famous or got loads of money, you can get away with it 9/10, just like with regular sex. But for regular joes, yeah, I do agree with anon that it's best to minimize your exposure. Specially with people you're close with.
Though I agree with you. Well-kept feet are a good indication a girl might be okay with a foot fetish.