Allow me to jump in here, (delayed, sorry) because this is central to a lot of the discussions here and very interesting. How can anyone know anything, really? All we know is the feelings and sensations we have, and IME you can experience things in a very clear way which is not with your logic mind or thinking, and though you cannot explain it in the terms of the 'other' system, it is no less real.
I see your point here. But personally I think that these feelings or spirtual needs or whatever you choose to call them, are not primarily of the flesh, although with us they are usually expressed in the flesh as well as in other ways. But they are not, as I see it, originally of the flesh. I am afraid I find it difficult to make to clear, but, well - the biggest sex organ is the mind - and, as I see it, the spirit.God/supplicant relationship which is not unlike the Master/sub relationship. And it seems to me that, since these religions tend to frown upon sensuality and sexuality in the flesh, it would only be natural for some to seek it out in their "spiritual" lives. Personally, I'll take it in the flesh!